View Filing Data

Three months ended September 30,

(Shares in thousands)

Stock options

Document and Entity Information - shares	9 Months Ended
Document and Entity Information - shares	Sep. 30, 2014	Oct. 16, 2014
Entity Information [Line Items]
Entity Registrant Name	REGENERON PHARMACEUTICALS INC
Entity Central Index Key	0000872589
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Sep. 30, 2014
Document Fiscal Year Focus	2014
Document Fiscal Period Focus	Q3
Amendment Flag	false
Common Stock
Entity Information [Line Items]
Entity Common Stock, Shares Outstanding		99,691,909
Class A Stock
Entity Information [Line Items]
Entity Common Stock, Shares Outstanding		1,973,368

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Sep. 30, 2014	Dec. 31, 2013
Current assets:
Cash and cash equivalents	$ 646,554	$ 535,608
Marketable securities	395,650	158,376
Accounts receivable - trade, net	673,915	787,071
Accounts Receivable from Sanofi	110,720	104,707
Accounts receivable from Bayer HealthCare	142,619	63,189
Inventories	120,317	70,354
Deferred tax assets	49,005	44,677
Prepaid expenses and other current assets	61,732	32,952
Total current assets	2,200,512	1,796,934
Marketable securities	453,443	389,891
Property, plant, and equipment, at cost, net of accumulated depreciation and amortization	818,967	526,983
Deferred tax assets	263,081	231,878
Other assets	3,416	5,327
Total assets	3,739,419	2,951,013
Current liabilities:
Accounts payable and accrued expenses	337,976	250,896
Deferred revenue from Sanofi, current portion	13,368	12,815
Deferred revenue - other, current portion	57,604	34,185
Facility lease obligations, current portion	1,252	939
Total current liabilities	410,200	298,835
Deferred revenue from Sanofi	75,283	76,522
Deferred Revenue - other	114,339	107,677
Facility lease obligations	276,112	184,258
Convertible senior notes	287,950	320,315
Other long-term liabilities	23,747	11,330
Total liabilities	1,187,631	998,937
Stockholders' equity:
Preferred Stock	0	0
Additional paid-in capital	2,423,434	2,045,857
Retained earnings (accumulated deficit)	145,206	(92,692)
Accumulated other comprehensive income (loss)	26,895	(1,188)
Treasury stock	(43,849)	0
Total stockholders' equity	2,551,788	1,952,076
Total liabilities and stockholders' equity	3,739,419	2,951,013
Class A Stock
Stockholders' equity:
Common stock	2	2
Common Stock
Stockholders' equity:
Common stock	100	97
Treasury Stock
Stockholders' equity:
Total stockholders' equity	$ (43,849)	$ 0

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Sep. 30, 2014	Dec. 31, 2013
Stockholders' equity:
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	30,000,000	30,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Treasury Stock, shares outstanding (in shares)	521,892	0
Class A Stock
Stockholders' equity:
Common Stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common Stock, shares authorized (in shares)	40,000,000	40,000,000
Common Stock, shares issued (in shares)	1,973,368	2,020,481
Common Stock, shares outstanding (in shares)	1,973,368	2,020,481
Common Stock
Stockholders' equity:
Common Stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common Stock, shares authorized (in shares)	160,000,000	160,000,000
Common Stock, shares issued (in shares)	100,195,822	97,666,814
Common Stock, shares outstanding (in shares)	100,195,822	97,666,814

CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Revenues:
Net product sales	$ 448,844	$ 367,118	$ 1,229,244	$ 1,019,751
Sanofi collaboration revenue	132,925	134,359	406,028	319,161
Bayer HealthCare collaboration revenue	135,853	88,583	358,460	134,594
Technology licensing and other revenue	8,166	6,967	23,496	20,827
Total revenues	725,788	597,027	2,017,228	1,494,333
Expenses:
Research and development	337,728	224,045	919,608	591,807
Selling, general, and administrative	149,748	97,607	361,012	247,330
Cost of goods sold	33,655	28,253	91,073	83,557
Cost of collaboration manufacturing	21,938	10,320	54,471	23,684
Total expenses	543,069	360,225	1,426,164	946,378
Income from operations	182,719	236,802	591,064	547,955
Other income (expense):
Investment and other income	2,591	618	5,205	2,028
Interest expense	(9,232)	(11,736)	(31,022)	(34,776)
Loss on extinguishment of debt	0	0	(10,787)	0
Total other income (expense)	(6,641)	(11,118)	(36,604)	(32,748)
Income before income taxes	176,078	225,684	554,460	515,207
Income tax expense	(96,358)	(84,378)	(316,562)	(187,651)
Net income	$ 79,720	$ 141,306	$ 237,898	$ 327,556
Net income per share - basic	$ 0.79	$ 1.44	$ 2.37	$ 3.36
Net income per share - diluted	$ 0.70	$ 1.25	$ 2.10	$ 2.95
Weighted average shares outstanding - basic	100,796	98,226	100,325	97,602
Weighted average shares outstanding - diluted	117,423	116,713	113,203	115,554
Statements of Comprehensive Income
Net income	$ 79,720	$ 141,306	$ 237,898	$ 327,556
Other comprehensive income (loss):
Unrealized gain (loss) on marketable securities, net of tax	22,632	578	28,083	(1,685)
Comprehensive income	$ 102,352	$ 141,884	$ 265,981	$ 325,871

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Retained Earnings (Accumulated Deficit)	Treasury Stock	Accumulated Other Comprehensive Income (Loss)	Class A Stock Common Stock
Balance at Dec. 31, 2012	$ 1,245,385	$ 95	$ 1,763,508	$ (517,054)	$ 0	$ (1,166)	$ 2
Balance (shares) at Dec. 31, 2012		95,223			0		2,069
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of Common Stock in connection with exercise of stock options	42,625	$ 3	42,622
Issuance of Common Stock in connection with exercise of stock options (shares)		2,641
Common Stock tendered upon exercise of stock options in connection with employee tax obligations	(166,358)	$ (1)	(166,357)
Common Stock tendered upon exercise of stock options in connection with employee tax obligations (in shares)		(597)
Issuance of Common Stock in connection with Company 401(k) Savings Plan contribution	0	$ 0
Issuance of Common Stock in connection with Company 401(k) Savings Plan contribution (in shares)		38
Issuance of restricted Common Stock under Long-Term Incentive Plan	0	$ 0
Issuance of restricted Common Stock under Long-Term Incentive Plan (in shares)		6
Conversion of Class A Stock to Common Stock (in shares)		40					(40)
Stock-based compensation charges	144,808		144,808
Excess tax benefit from stock-based compensation	97,840		97,840
Net income	327,556
Other comprehensive income, net of tax	(1,685)					(1,685)
Balance at Sep. 30, 2013	1,690,171	$ 97	1,882,421	(189,498)	$ 0	(2,851)	$ 2
Balance (shares) at Sep. 30, 2013		97,351			0		2,029
Balance at Dec. 31, 2013	1,952,076	$ 97	2,045,857	(92,692)	$ 0	(1,188)	$ 2
Balance (shares) at Dec. 31, 2013		97,667			0		2,020
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of Common Stock in connection with exercise of stock options	79,698	$ 3	79,695
Issuance of Common Stock in connection with exercise of stock options (shares)		2,460
Common Stock tendered upon exercise of stock options in connection with employee tax obligations	(175,866)	$ 0	(175,866)
Common Stock tendered upon exercise of stock options in connection with employee tax obligations (in shares)		(526)
Issuance of Common Stock in connection with conversion of convertible senior notes	156,373	$ 0	156,373
Issuance of Common Stock in connection with conversion of convertible senior notes (in shares)		522
Issuance of Common Stock in connection with Company 401(k) Savings Plan contribution	0	$ 0
Issuance of Common Stock in connection with Company 401(k) Savings Plan contribution (in shares)		21
Issuance of restricted Common Stock under Long-Term Incentive Plan	0	$ 0
Issuance of restricted Common Stock under Long-Term Incentive Plan (in shares)		5
Conversion of Class A Stock to Common Stock (in shares)		47					(47)
Stock-based compensation charges	229,692		229,692
Excess tax benefit from stock-based compensation	343,532		343,532
Acquisition of Common Stock in connection with exercise of convertible note hedges	0		43,849		$ (43,849)
Acquisition of Common Stock in connection with exercise of convertible note hedges (in shares)					(522)
Reduction of warrants in connection with conversion of senior notes	(143,041)		(143,041)
Reduction of equity component of convertible senior notes	(156,657)		(156,657)
Net income	237,898			237,898
Other comprehensive income, net of tax	28,083					28,083
Balance at Sep. 30, 2014	$ 2,551,788	$ 100	$ 2,423,434	$ 145,206	$ (43,849)	$ 26,895	$ 2
Balance (shares) at Sep. 30, 2014		100,196			(522)		1,973

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013
Cash flows from operating activities:
Net income	$ 237,898	$ 327,556
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	38,551	29,912
Non-cash compensation expense	225,784	143,217
Non-cash interest expense	15,629	17,316
Losses on Extinguishment of Debt	10,787	0
Other non-cash charges and expenses, net	12,844	15,710
Deferred taxes	(50,466)	82,890
Changes in assets and liabilites
Decrease (increase) in Sanofi, Bayer HealthCare, and trade accounts receivable	27,713	(350,809)
Increase in Inventories	(50,917)	(36,742)
(Increase) decrease in prepaid expenses and other assets	(28,850)	3,738
Increase (decrease) in deferred revenue	29,395	(20,815)
Increase in accounts payable, accrued expenses and other liabilities	76,506	94,894
Total adjustments	306,976	(20,689)
Net cash provided by operating activities	544,874	306,867
Cash flows from investing activities:
Purchases of marketable securities	(478,436)	(477,312)
Sales or maturities of marketable securities	216,478	319,152
Capital expenditures	(215,464)	(87,347)
Net cash used in investing activities	(477,422)	(245,507)
Cash flows from financing activities:
Payments in connection with facility and capital lease obligations	(810)	(1,625)
Repayments of convertible senior notes	(61,125)	0
Payments in connection with deduction of outstanding warrants	(143,041)	0
Proceeds from issuance of Common Stock	80,804	41,718
Payments in connection with Common Stock tendered for employee tax obligations	(175,866)	(166,358)
Excess tax benefit from stock-based compensation	343,532	97,840
Net cash provided by (used in) financing activities	43,494	(28,425)
Net increase in cash and cash equivalents	110,946	32,935
Cash and cash equivalents at beginning of period	535,608	230,276
Cash and cash equivalents at end of period	$ 646,554	$ 263,211

Interim Financial Statements (Notes)	9 Months Ended
Interim Financial Statements (Notes)	Sep. 30, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Interim Financial Statements	Interim Financial Statements The interim Condensed Consolidated Financial Statements of Regeneron Pharmaceuticals, Inc. ("Regeneron" or the "Company") have been prepared in accordance with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all information and disclosures necessary for a presentation of the Company’s financial position, results of operations, and cash flows in conformity with accounting principles generally accepted in the United States of America. In the opinion of management, these financial statements reflect all normal recurring adjustments and accruals necessary for a fair statement of the Company’s financial position, results of operations, and cash flows for such periods. The results of operations for any interim periods are not necessarily indicative of the results for the full year. The December 31, 2013 Condensed Consolidated Balance Sheet data were derived from audited financial statements, but do not include all disclosures required by accounting principles generally accepted in the United States of America. These financial statements should be read in conjunction with the financial statements and notes thereto contained in the Company’s Annual Report on Form 10-K for the year ended December 31, 2013. Certain reclassifications have been made to prior period amounts to conform with the current period’s presentation.

- Definition

The entire disclosure for organization, consolidation and basis of presentation of financial statements disclosure.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-URI http://asc.fasb.org/subtopic&trid=2134480

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 852
-SubTopic 10
-URI http://asc.fasb.org/subtopic&trid=2209116

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-URI http://asc.fasb.org/subtopic&trid=2197480

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 10
-URI http://asc.fasb.org/subtopic&trid=2122150

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=28200181&loc=SL6228881-111685

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 720
-SubTopic 15
-URI http://asc.fasb.org/subtopic&trid=2122524

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 915
-SubTopic 235
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6472506&loc=d3e38932-110933

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 10
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=7668296&loc=d3e288-107754

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6367646&loc=d3e18780-107790

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=18733093&loc=d3e5614-111684

Reference 12: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6359566&loc=d3e326-107755

+ Details

Net Product Sales (Notes)

9 Months Ended

Sep. 30, 2014

Revenues [Abstract]

Product Sales and Concentration Risk [Text Block]

Product Sales

EYLEA^® net product sales in the United States totaled $445.0 million and $363.1 million for the three months ended September 30, 2014 and 2013, respectively, and $1,218.8 million and $1,006.8 million for the nine months ended September 30, 2014 and 2013, respectively. In addition, ARCALYST^® net product sales totaled $3.8 million and $4.0 million for the three months ended September 30, 2014 and 2013, respectively, and $10.4 million and $12.9 million for the nine months ended September 30, 2014 and 2013, respectively.

The Company recorded 72% and 75% for the three months ended September 30, 2014 and 2013, respectively, and 75% and 76% for the nine months ended September 30, 2014 and 2013, respectively, of its total gross product revenue from sales to Besse Medical, a subsidiary of AmerisourceBergen Corporation.

Revenue from product sales is recorded net of applicable provisions for rebates and chargebacks under governmental programs, distribution-related fees, prompt pay discounts, and other sales-related deductions. The following table summarizes the provisions, and credits/payments, for these sales-related deductions during the nine months ended September 30, 2014.



	Rebates & Chargebacks			Distribution- Related Fees			Other Sales- Related Deductions			Total
Balance as of December 31, 2013	$	4,400		$	19,663		$	538		$	24,601
Provision related to current period sales	23,265			53,689			1,202			78,156
Credits/payments	(23,873		)	(54,878		)	(1,211		)	(79,962		)
Balance as of September 30, 2014	$	3,792		$	18,474		$	529		$	22,795

Under the provisions of the Patient Protection and Affordable Care Act ("PPACA") and the Health Care and Education Reconciliation Act of 2010, a non-tax deductible annual fee (the "Branded Prescription Drug Fee") is imposed on pharmaceutical manufacturers that sell branded prescription drugs to specified government programs. The legislation imposed an annual fee on companies for each calendar year beginning in 2011. This fee is allocated to companies based on their prior year market share of total branded prescription drug sales into these government programs. Orphan drugs sales, including ARCALYST, are not subject to the fee. In July 2014, the Internal Revenue Service ("IRS") issued final regulations that provide guidance on the Branded Prescription Drug Fee. The final regulations differ in some respects from the temporary regulations issued by the IRS in 2011, including that a company is liable for the fee based on its branded prescription drug sales in the current year, instead of the liability only being applicable upon the first qualifying branded prescription drug sale of the following fee year under the temporary regulations. As a result of the issuance of these final IRS regulations, the Company will record an estimate of the fee in the same period in which its qualifying branded prescription drug sales occur. Therefore, in the third quarter of 2014, an incremental charge was recorded to (i) recognize a liability for the estimated fee payable based on 2014 sales through the first nine months of 2014, and (ii) expense the remaining prepaid asset recorded under the previous accounting for the estimated fee payable based on 2013 sales. The impact of the incremental charge in the third quarter was $40.6 million, which was included in selling, general, and administrative expenses.

Collaboration Agreements (Notes)

9 Months Ended

Sep. 30, 2014

Collaboration Agreement [Abstract]

Collaboration Agreements

Sanofi

Sanofi collaboration revenue, as detailed below, consisted primarily of reimbursement for research and development expenses that the Company incurred, partly offset by sharing of pre-launch commercialization expenses in connection with the companies' antibody collaboration. In addition, Sanofi collaboration revenue for the nine months ended September 30, 2013 was reduced by two $10.0 million up-front payments to Sanofi in connection with the Company's acquisition from Sanofi of full exclusive rights to two families of novel antibodies, as described below.



	Three months ended September 30,
Sanofi Collaboration Revenue	2014			2013
ZALTRAP:
Regeneron's share of losses in connection with commercialization of ZALTRAP	$	(1,008	)	$	(6,575	)
Reimbursement of Regeneron research and development expenses	1,261			1,316
Other	756			2,625
Total ZALTRAP	1,009			(2,634		)
Antibody:
Reimbursement of Regeneron research and development expenses	140,497			133,128
Regeneron's share of commercialization expenses	(12,830		)	—
Other	4,249			3,865
Total Antibody	131,916			136,993
Total Sanofi collaboration revenue	$	132,925		$	134,359



	Nine months ended September 30,
Sanofi Collaboration Revenue	2014			2013
ZALTRAP:
Regeneron's share of losses in connection with commercialization of ZALTRAP	$	(4,912	)	$	(22,581	)
Reimbursement of Regeneron research and development expenses	3,691			5,497
Other	4,417			6,610
Total ZALTRAP	3,196			(10,474		)
Antibody:
Reimbursement of Regeneron research and development expenses	405,212			338,027
Regeneron's share of commercialization expenses	(17,125		)	—
Up-front payments to Sanofi for acquisition of rights related to two antibodies	—			(20,000		)
Other	14,745			11,608
Total Antibody	402,832			329,635
Total Sanofi collaboration revenue	$	406,028		$	319,161

Sanofi commenced sales of ZALTRAP^® (ziv-aflibercept) Injection for Intravenous Infusion, in combination with 5-fluorouracil, leucovorin, irinotecan ("FOLFIRI"), for patients with metastatic colorectal cancer that is resistant to or has progressed following an oxaliplatin-containing regimen, in the United States in the third quarter of 2012 and in certain European and other countries in the first quarter of 2013. The Company and Sanofi globally collaborate on the development and commercialization of ZALTRAP. Under the terms of the companies' September 2003 collaboration agreement, as amended, Regeneron and Sanofi share co-promotion rights and profits and losses on sales of ZALTRAP outside of Japan. The Company is entitled to receive a percentage of sales of ZALTRAP in Japan.

Under the Company's antibody collaboration agreement with Sanofi, agreed upon worldwide development expenses incurred by both companies during the term of the agreement are funded by Sanofi, except that following receipt of the first positive Phase 3 trial results for a co-developed drug candidate, which first occurred in the fourth quarter of 2013, subsequent Phase 3 trial-related costs for that drug candidate ("Shared Phase 3 Trial Costs") are shared 80% by Sanofi and 20% by Regeneron. Consequently, during the three and nine months ended September 30, 2014, the Company recognized as additional research and development expense $28.4 million and $81.3 million, respectively, of antibody development expenses that the Company was obligated to reimburse to Sanofi related to alirocumab and sarilumab.

Effective in the second quarter of 2014, the Company and Sanofi began sharing pre-launch commercialization expenses related to alirocumab in accordance with the companies’ antibody collaboration agreement.

In May 2013, the Company acquired from Sanofi full exclusive rights to two families of novel antibodies invented at Regeneron and previously included in the Company's antibody collaboration with Sanofi. The Company acquired full rights to antibodies targeting the platelet derived growth factor (PDGF) family of receptors and ligands in ophthalmology and all other indications and to antibodies targeting the angiopoietin-2 (Ang2) receptor and ligand in ophthalmology. With respect to PDGF antibodies, the Company made a $10.0 million up-front payment to Sanofi in the second quarter of 2013. In addition, with respect to Ang2 antibodies in ophthalmology, the Company made a $10.0 million up-front payment to Sanofi in the second quarter of 2013.

With respect to PDGF antibodies, the Company made two $5.0 million development milestone payments to Sanofi in the first quarter of 2014, which were recorded in the Company's Statements of Operations as research and development expense. The Company is also obligated to pay up to $30.0 million in additional potential development milestones as well as royalties on any future sales of PDGF antibodies.

In July 2014, in connection with the Company’s antibody collaboration with Sanofi, the Company purchased a U.S. Food and Drug Administration ("FDA") priority review voucher from a third party for $67.5 million. The Company and Sanofi equally shared the priority review voucher's purchase price, and the Company's share of the cost, or $33.8 million, was recorded as a research and development expense during the third quarter of 2014. The Company subsequently transferred the voucher to Sanofi, which intends to use the priority review voucher in connection with a planned Biologics License Application submission to the FDA for alirocumab.

Bayer HealthCare LLC

The Company and Bayer HealthCare globally collaborate on the development and commercialization of EYLEA outside of the United States. Bayer HealthCare commenced sales of EYLEA outside the United States for the treatment of wet AMD in the fourth quarter of 2012, for the treatment of macular edema secondary to CRVO in the fourth quarter of 2013, and for the treatment of DME in the third quarter of 2014. In addition, in January 2014, the Company entered into a license and collaboration agreement with Bayer HealthCare governing the joint development and commercialization outside the United States of an antibody product candidate to Platelet Derived Growth Factor Receptor Beta (PDGFR-beta).

The collaboration revenue the Company earned from Bayer HealthCare is detailed below:



	Three months ended September 30,
Bayer HealthCare Collaboration Revenue	2014		2013
EYLEA:
Regeneron's net profit in connection with commercialization of EYLEA outside the United States	$	85,351	$	31,769
Sales and substantive development milestones	30,000		45,000
Cost-sharing of Regeneron EYLEA development expenses	4,394		3,739
Other	12,745		8,075
Total EYLEA	132,490		88,583
PDGFR-beta antibody:
Cost-sharing of REGN2176-3 development expenses	518		—
Other	2,845		—
Total PDGFR-beta	3,363		—
Total Bayer HealthCare collaboration revenue	$	135,853	$	88,583



	Nine months ended September 30,
Bayer HealthCare Collaboration Revenue	2014		2013
EYLEA:
Regeneron's net profit in connection with commercialization of EYLEA outside the United States	$	213,291	$	57,186
Sales and substantive development milestones	75,000		45,000
Cost-sharing of Regeneron EYLEA development expenses	26,235		13,207
Other	34,490		19,201
Total EYLEA	349,016		134,594
PDGFR-beta antibody:
Cost-sharing of REGN2176-3 development expenses	1,657		—
Other	7,787		—
Total PDGFR-beta	9,444		—
Total Bayer HealthCare collaboration revenue	$	358,460	$	134,594

EYLEA

During the nine months ended September 30, 2014, the Company earned, and recorded as revenue, five $15.0 million sales milestones (two of which were recorded in the third quarter of 2014) from Bayer HealthCare upon total aggregate net sales of EYLEA outside the United States exceeding $500 million, $600 million, $700 million, $800 million, and $900 million, respectively, over a twelve-month period. The Company is eligible to receive one additional $15.0 million sales milestone payment if twelve-month sales of EYLEA outside the United States exceed $1 billion. In addition, in connection with a November 2013 agreement under which Bayer HealthCare obtained rights to use certain of the Company’s EYLEA clinical data for a regulatory filing, the Company became eligible to receive up to $30.0 million in additional sales milestone payments if twelve-month sales of specific commercial supplies of EYLEA outside the United States achieve certain specified levels up to $200 million.

In January 2014, Bayer HealthCare decided to participate in the global development and commercialization of EYLEA outside the United States for the treatment of macular edema following branch retinal vein occlusion ("BRVO"). In connection with this decision, Bayer HealthCare reimbursed Regeneron $15.7 million for a defined share of the EYLEA global development costs that the Company had incurred prior to February 2014 for the BRVO indication, which was recognized as Bayer HealthCare collaboration revenue in the first quarter of 2014 and is included with "Cost-sharing of Regeneron EYLEA development expenses" for the nine months ended September 30, 2014 in the table above. In addition, all future agreed upon global EYLEA development expenses incurred in connection with BRVO are being shared equally, and any future profits or losses on sales of EYLEA outside of the United States for the treatment of macular edema following BRVO will also be shared (for countries other than Japan). The Company is entitled to receive a tiered percentage of EYLEA net sales in Japan.

PDGFR-beta Antibody

In January 2014, the Company also entered into an agreement with Bayer HealthCare governing the joint development and commercialization outside the United States of an antibody product candidate to PDGFR-beta, including in combination with EYLEA, for the treatment of ocular diseases or disorders. REGN2176-3, a combination product candidate comprised of an antibody to PDGFR-beta co-formulated with EYLEA, is being developed under the agreement. Under the agreement, the Company will conduct the initial development of the PDGFR-beta antibody through completion of the first proof-of-concept study, upon which Bayer HealthCare will have a right to opt-in to license and collaborate on further development and commercialization outside the United States.

In connection with the agreement, Bayer HealthCare made a $25.5 million non-refundable upfront payment to the Company in January 2014, and is obligated to pay 25% of global development costs and 50% of development costs exclusively for the territory outside the United States under the initial development plan. In addition, Bayer HealthCare is obligated to reimburse the Company for 50% of development milestone payments to Sanofi related to the Company's acquisition of rights to antibodies targeting the PDGF family of receptors in May 2013, as described above. In that regard, Bayer HealthCare made two $2.5 million development milestone payments to the Company in the first quarter of 2014 (both of which, for the purpose of revenue recognition, were not considered substantive). Further, in connection with the Company’s initial development of the PDGFR-beta antibody through completion of the first proof-of-concept study, the Company is eligible to receive up to $15.0 million in future development milestone payments from Bayer HealthCare, although certain of these development milestone payments could be reduced by half if Bayer HealthCare does not opt-in to the collaboration.

From inception of the agreement until Bayer HealthCare has the right to opt-in to the collaboration, the Company's sole significant deliverable is research and development services provided in accordance with the agreement. Therefore, the $25.5 million upfront payment was allocated to this deliverable, initially recorded as deferred revenue, and will be recognized as revenue over the related performance period. In addition, the two $2.5 million non-substantive development milestone payments from Bayer HealthCare were also initially recorded as deferred revenue and will be recognized over the same performance period as the upfront payment.

If Bayer HealthCare exercises its right to opt-in to the collaboration, it will obtain exclusive commercialization rights to the product outside the United States, continue to pay for 25% of global development costs and 50% of development costs exclusively for the territory outside the United States, pay a $20.0 million opt-in payment to the Company, pay a $20.0 million development milestone to the Company upon receipt of the first marketing approval in the European Union or Japan, share profits and losses from sales outside the United States equally with the Company, and be responsible for the payment of royalties on sales outside the United States to Sanofi.

Within the United States, the Company has exclusive commercialization rights and will retain all of the profits from sales. If Bayer HealthCare does not opt-in to the collaboration, the Company will have exclusive rights to develop and commercialize PDGFR-beta antibodies (except as a combination product with EYLEA) for use outside the United States.

The Company also has the right to opt-out of the collaboration upon completion of the first proof-of-concept study for the PDGFR-beta antibody. If the Company opts-out of the collaboration and Bayer HealthCare exercises its right to opt-in to the collaboration, Bayer HealthCare will obtain exclusive rights to the PDGFR-beta antibody (except as a combination product with EYLEA) outside of the United States, be responsible for all development costs outside of the United States, be responsible for all royalty and milestone payments to a third party, and will retain all of the profits from sales of the PDGFR-beta antibody outside of the United States.

Unless terminated earlier in accordance with its provisions, the agreement will continue to be in effect until such time as neither party or its respective affiliates or sublicensees is developing or commercializing a PDGFR-beta antibody in the specified field outside of the United States and such discontinuation is acknowledged as permanent by both the Company and Bayer HealthCare in writing.

Avalanche Biotechnologies, Inc.

In May 2014, the Company entered into a research collaboration and license agreement with Avalanche Biotechnologies, Inc. to discover, develop, and commercialize novel gene therapy products for the treatment of ophthalmologic diseases. In connection with the agreement, the Company made a $2.0 million upfront payment and a $6.0 million pre-payment of collaboration research costs, and is obligated to pay potential additional research costs, an aggregate amount of up to $80.0 million per product upon meeting certain potential development and regulatory milestones (for products directed to as many as eight therapeutic targets, or up to an aggregate of $640.0 million), and royalties on any future sales of such products. The Company also purchased an aggregate of $5.0 million of Avalanche preferred stock. Under the agreement, the Company will collaborate with Avalanche to conduct research for the discovery of novel gene therapy vectors. Subsequent to the filing of an Investigational New Drug application ("IND") with the FDA for a product candidate developed under the agreement, Regeneron may exercise its right to obtain exclusive worldwide rights to further research, develop, and commercialize such product candidates directed to the applicable therapeutic target. In addition, Avalanche has the option to share in development costs and profits for products directed toward up to two therapeutic targets of its choice.

In July 2014, Avalanche commenced an initial public offering ("IPO") of its common stock and thereby triggered the Company's obligation under the research collaboration and license agreement to purchase up to $10.0 million of Avalanche common stock in a concurrent private placement. As part of the concurrent private placement, the Company purchased from Avalanche at the closing of the IPO 588,235 shares of Avalanche common stock for an aggregate purchase price of $10.0 million. In addition, at the closing of the IPO, Avalanche preferred stock, including the Avalanche preferred stock held by the Company, automatically converted on a one-for-one basis into Avalanche common stock.

Net Income Per Share (Notes)

9 Months Ended

Sep. 30, 2014

Earnings Per Share [Abstract]

Net Income Per Share

The Company’s basic net income per share amounts have been computed by dividing net income by the weighted average number of shares of Common Stock and Class A Stock outstanding. Net income per share is presented on a combined basis, inclusive of Common Stock and Class A Stock outstanding, as each class of stock has equivalent economic rights. Diluted net income per share includes the potential dilutive effect of other securities as if such securities were converted or exercised during the period, when the effect is dilutive. The calculations of basic and diluted net income per share are as follows:



	Three months ended September 30,
	2014		2013
Net income - basic	$	79,720	$	141,306
Effective of dilutive securities:
Convertible senior notes - interest expense related to contractual coupon interest rate and amortization of discount and note issuance costs	2,803		4,678
Net income - diluted	$	82,523	$	145,984

(Shares in thousands)
Weighted average shares - basic	100,796		98,226
Effect of dilutive securities:
Stock options	9,377		10,379
Restricted stock	430		462
Convertible senior notes	4,033		4,761
Warrants	2,787		2,885
Dilutive potential shares	16,627		18,487
Weighted average shares - diluted	117,423		116,713

Net income per share - basic	$	0.79	$	1.44
Net income per share - diluted	$	0.70	$	1.25



	Nine months ended September 30,
	2014		2013
Net income - basic	$	237,898	$	327,556
Effective of dilutive securities:
Convertible senior notes - interest expense related to contractual coupon interest rate and amortization of discount and note issuance costs	—		13,857
Net income - diluted	$	237,898	$	341,413

(Shares in thousands)
Weighted average shares - basic	100,325		97,602
Effect of dilutive securities:
Stock options	9,515		10,220
Restricted stock	413		415
Convertible senior notes	—		4,761
Warrants	2,950		2,556
Dilutive potential shares	12,878		17,952
Weighted average shares - diluted	113,203		115,554

Net income per share - basic	$	2.37	$	3.36
Net income per share - diluted	$	2.10	$	2.95

Shares which have been excluded from the September 30, 2014 and 2013 diluted per share amounts because their effect would have been antidilutive include the following:

Marketable Securities (Notes)

9 Months Ended

Sep. 30, 2014

Investments, Debt and Equity Securities [Abstract]

Marketable Securities

Marketable securities at September 30, 2014 and December 31, 2013 consist of both debt securities issued by investment grade institutions as well as equity securities. The Company also held restricted marketable securities as of September 30, 2014, consisting of the Company's investment in Avalanche common shares (see Note 3), which are subject to customary transfer restrictions until January 2015 under a lock-up agreement with the underwriters of Avalanche's IPO.

The following tables summarize the Company's investments in marketable securities at September 30, 2014 and December 31, 2013.



	Amortized		Unrealized					Fair
At September 30, 2014	Cost Basis		Gains		Losses			Value
Unrestricted
U.S. government and government agency obligations	$	51,059	$	71	$	(1	)	$	51,129
Corporate bonds	696,149		574		(1,131		)	695,592
Municipal bonds	42,756		94		(8		)	42,842
Equity securities	1,166		3,933		—			5,099
	791,130		4,672		(1,140		)	794,662
Restricted
Equity securities	15,000		39,431		—			54,431
	$	806,130	$	44,103	$	(1,140	)	$	849,093

At December 31, 2013
Unrestricted
U.S. government and government agency obligations	$	107,493	$	55	$	(27	)	$	107,521
Corporate bonds	369,321		233		(361		)	369,193
Commercial paper	23,891		53		—			23,944
Municipal bonds	36,935		45		(59		)	36,921
International government agency obligations	2,007		1		—			2,008
Certificates of deposit	7,509		5		—			7,514
Equity securities	1,166		—		—			1,166
	$	548,322	$	392	$	(447	)	$	548,267

The Company classifies its debt security investments based on their contractual maturity dates. The debt securities listed at September 30, 2014 mature at various dates through August 2024. The fair values of debt security investments by contractual maturity as of September 30, 2014 and December 31, 2013 consist of the following:



	September 30, 2014		December 31, 2013
Maturities within one year	$	287,739	$	158,376
Maturities after one year through five years	496,700		383,410
Maturities after five years through ten years	5,124		4,138
Maturities after ten years	—		1,177
	$	789,563	$	547,101

The following table shows the fair value of the Company’s marketable securities that have unrealized losses and that are deemed to be only temporarily impaired, aggregated by investment category and length of time that the individual securities have been in a continuous unrealized loss position, at September 30, 2014 and December 31, 2013.



	Less than 12 Months					12 Months or Greater		Total
At September 30, 2014	Fair Value		Unrealized Loss			Fair Value	Unrealized Loss	Fair Value		Unrealized Loss
U.S. government and government agency obligations	$	1,401	$	(1	)	—	—	$	1,401	$	(1	)
Corporate bonds	343,835		(1,131		)	—	—	343,835		(1,131		)
Municipal bonds	10,502		(8		)	—	—	10,502		(8		)
	$	355,738	$	(1,140	)	—	—	$	355,738	$	(1,140	)

At December 31, 2013
U.S. government and government agency obligations	$	49,241	$	(27	)	—	—	$	49,241	$	(27	)
Corporate bonds	176,140		(361		)	—	—	176,140		(361		)
Municipal bonds	14,431		(59		)	—	—	14,431		(59		)
	$	239,812	$	(447	)	—	—	$	239,812	$	(447	)

Realized gains and losses are included as a component of investment income. For both the three and nine months ended September 30, 2014, total realized gains and losses on sales of marketable securities were not material. For both the three and nine months ended September 30, 2013, total realized gains on sales of marketable securities were $0.5 million and $1.0 million, respectively, and there were no realized losses. Changes in the Company's accumulated other comprehensive income (loss) for the three and nine months ended September 30, 2014 and 2013 related to unrealized gains and losses on available-for-sale marketable securities. For the three and nine months ended September 30, 2014 and 2013, amounts reclassified from accumulated other comprehensive income (loss) into investment income in the Company's Statements of Operations were related to realized gains and losses on sales of marketable securities.

- Definition

The entire disclosure for investments in certain debt and equity securities.

+ References + Details

Fair Value Measurements (Notes)

9 Months Ended

Sep. 30, 2014

Fair Value Disclosures [Abstract]

Fair Value Measurements

The Company’s assets that are measured at fair value on a recurring basis, at September 30, 2014 and December 31, 2013, consist of the following:



			Fair Value Measurements at Reporting Date Using
At September 30, 2014	Fair Value		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)
Available-for-sale marketable securities:
Unrestricted
U.S. government and government agency obligations	$	51,129	—		$	51,129
Corporate bonds	695,592		—		695,592
Municipal bonds	42,842		—		42,842
Equity securities	5,099		$	5,099	—
	794,662		5,099		789,563
Restricted
Equity securities	54,431		—		54,431
	$	849,093	$	5,099	$	843,994

At December 31, 2013
Available-for-sale marketable securities:
Unrestricted
U.S. government and government agency obligations	$	107,521	—		$	107,521
Corporate bonds	369,193		—		369,193
Commercial paper	23,944		—		23,944
Municipal bonds	36,921		—		36,921
International government agency obligations	2,008		—		2,008
Certificates of deposit	7,514		—		7,514
Equity securities	1,166		$	1,166	—
	$	548,267	$	1,166	$	547,101

Marketable securities included in Level 2 are valued using quoted market prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active, or model-based valuations in which significant inputs used are observable. The Company considers market liquidity in determining the fair value for these securities. The Company did not record any charges for other-than-temporary impairment of its Level 2 marketable securities during the three and nine months ended September 30, 2014 and 2013.

During the three months ended September 30, 2013, the Company sold a Level 3 marketable security and realized a $0.4 million gain on its sale. There were no other sales, or purchases or maturities of, Level 3 marketable securities and no unrealized gains or losses related to Level 3 marketable securities for the three and nine months ended September 30, 2014 and 2013. There were no transfers of marketable securities between Levels 1, 2, or 3 classifications during the three and nine months ended September 30, 2014 and 2013.

As of September 30, 2014 and December 31, 2013, the Company had $338.9 million and $400.0 million, respectively, in aggregate principal amount of 1.875% convertible senior notes (the "Notes") that will mature on October 1, 2016 unless earlier converted or repurchased. As described in Note 9, a portion of the Notes was surrendered for conversion during the second quarter of 2014. The fair value of the outstanding Notes was estimated to be $1,433.8 million and $1,327.2 million as of September 30, 2014 and December 31, 2013, respectively, and was determined based on Level 2 inputs, such as market and observable sources.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Inventory (Notes)

9 Months Ended

Sep. 30, 2014

Inventory Disclosure [Abstract]

Inventory

Inventories

Inventories consist of the following:



	September 30,		December 31,
	2014		2013
Raw materials	$	10,170	$	9,120
Work-in-process	70,965		35,868
Finished goods	11,368		14,352
Deferred costs	27,814		11,014
	$	120,317	$	70,354

Deferred costs represent the costs of product manufactured and shipped to the Company's collaborators for which recognition of revenue has been deferred. For the three months ended September 30, 2014, cost of goods sold included inventory write-downs and reserves totaling $1.6 million; such amounts were not material for the three months ended September 30, 2013. For the nine months ended September 30, 2014 and 2013, cost of goods sold included inventory write-downs and reserves totaling $3.5 million and $4.8 million, respectively.

Accounts Payable and Accrued Expenses (Notes)

9 Months Ended

Sep. 30, 2014

Payables and Accruals [Abstract]

Accounts Payable and Accrued Expenses

Accounts payable and accrued expenses consist of the following:



	September 30,		December 31,
	2014		2013
Accounts payable	$	47,342	$	61,936
Accrued payroll and related costs	75,159		69,429
Accrued clinical trial expense	45,384		23,654
Accrued sales-related charges, deductions, and royalties	114,408		66,855
Other accrued expenses and liabilities	55,683		29,022
	$	337,976	$	250,896

Convertible Debt (Notes)	9 Months Ended
Convertible Debt (Notes)	Sep. 30, 2014
Debt Disclosure [Abstract]
Debt Disclosure [Text Block]	Convertible Debt In the second quarter of 2014, $61.1 million principal amount of the Company's $400.0 million aggregate principal amount of Notes were surrendered for conversion. In accordance with the terms of the Notes, the Company elected to settle these conversion obligations through a combination of cash, in an amount equal to the principal amount of the converted Notes, and shares of the Company's Common Stock in respect of any amounts due in excess thereof. Consequently, upon settlement of the Notes during the second quarter of 2014, the Company (i) paid $61.1 million in cash, (ii) issued 521,876 shares of Common Stock, (iii) recognized a $10.8 million loss on the debt extinguishment, and (iv) allocated $156.7 million of the settlement consideration provided to the Note holders to the reacquisition of the equity component of the Notes, and recognized such amount as a reduction of stockholder's equity. In connection with the initial offering of the Notes in October 2011, the Company entered into convertible note hedge and warrant transactions with multiple counterparties, which were recorded to additional paid-in capital. As a result of the Note conversions described above, in the second quarter of 2014 the Company exercised a proportionate amount of its convertible note hedges, for which the Company received 521,876 shares of Common Stock, which was equivalent to the number of shares the Company was required to issue to settle the non-cash portion of the related Note conversions. The shares received were recorded as Treasury Stock, at cost, in the Company's Balance Sheet and Statement of Stockholders' Equity. Also during the second quarter of 2014, the Company entered into agreements to reduce the number of warrants held by each of the warrant holders in proportion to the amount of Notes converted. Pursuant to the agreements, the Company paid an aggregate amount of $143.0 million to the warrant holders to reduce the maximum number of shares of Common Stock issuable upon exercise of the warrants from 4,760,840 to 4,033,324 (subject to adjustment from time to time as provided in the applicable warrant agreements). The remaining warrants expire, and will be exercisable, at various dates during 2017. In October 2014, the Company received notification that an additional $160.8 million principal amount of the Notes were surrendered for conversion, and settlement is anticipated during the fourth quarter of 2014. The Company elected to settle these conversion obligations through a combination of cash and shares (total payment will be based on the average of the volume-weighted-average prices of the Common Stock during the 40 trading-day cash settlement averaging period specified in the indenture governing the Notes). In connection with these Note conversions, the Company exercised a proportionate amount of its convertible note hedges, for which the Company expects to receive shares of Common Stock equivalent to the number of shares the Company will be required to issue to settle the non-cash portion of the related Note conversions.

Income Taxes (Notes)	9 Months Ended
Income Taxes (Notes)	Sep. 30, 2014
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The Company is subject to U.S. federal, state, and foreign income taxes. The Company recorded an income tax provision in its Statement of Operations of $96.4 million and $84.4 million for the three months ended September 30, 2014 and 2013, respectively, and $316.6 million and $187.7 million for the nine months ended September 30, 2014 and 2013, respectively. The Company's effective tax rate was 54.7% and 37.4% for the three months ended September 30, 2014 and 2013, respectively, and 57.1% and 36.4% for the nine months ended September 30, 2014 and 2013, respectively. The Company's effective tax rate for the three and nine months ended September 30, 2014 was negatively impacted by losses incurred in foreign jurisdictions with rates lower than the federal statutory rate, the incremental charge related to the non-tax deductible Branded Prescription Drug Fee (see Note 2), and expiration at the end of 2013 of the federal tax credit for increased research activities. In addition, the Company's effective tax rate for the nine months ended September 30, 2014 was negatively impacted by New York State tax legislation enacted in the first quarter of 2014. This tax legislation reduced the New York State income tax rate to zero percent for "qualified manufacturers", including Regeneron, effective in 2014; however, it also resulted in the Company reducing its related deferred tax assets as a discrete item in the first quarter of 2014. As a result, this tax legislation caused a net increase in the Company's effective tax rate of 2.2% for the nine months ended September 30, 2014. The Company's effective tax rate for the nine months ended September 30, 2013 included, as a discrete item in the first quarter of 2013, the favorable impact of the enactment of The American Taxpayer Relief Act in January 2013. The American Taxpayer Relief Act included a provision to extend the income tax credit for increased research activities retroactively to the tax year ended December 31, 2012, as well as for 2013. As a result, the Company's 2012 research tax credit reduced its effective tax rate for the nine months ended September 30, 2013 by 4.3%. The Company also recorded an income tax provision in its Statement of Comprehensive Income of $13.5 million and $14.9 million for the three and nine months ended September 30, 2014, respectively, in connection with the Company’s unrealized gains on “available-for-sale” marketable securities. For both the three and nine months ended September 30, 2013, no such income tax provision or benefit was required in connection with the Company’s unrealized gains (losses) on “available-for-sale” marketable securities. Tax years subsequent to 2010 remain open to examination by federal tax authorities. The Company's 2011 federal income tax return is currently under audit by the IRS. During the second quarter of 2014, New York State tax authorities finalized their audit of the Company's 2009, 2010, and 2011 business corporation franchise tax returns with no adjustments.

Statement of Cash Flows (Notes)	9 Months Ended
Statement of Cash Flows (Notes)	Sep. 30, 2014
Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract]
Statement of Cash Flows	Statement of Cash Flows Supplemental disclosure of non-cash investing and financing activities: Included in accounts payable and accrued expenses at September 30, 2014 and December 31, 2013 were $38.6 million and $16.1 million, respectively, of accrued capital expenditures primarily in connection with renovation of the Company's new Limerick, Ireland facility and expansion and renovations in its Rensselaer, New York manufacturing facilities. Included in accounts payable and accrued expenses at September 30, 2013 and December 31, 2012 were $18.4 million and $8.6 million, respectively, of accrued capital expenditures. Pursuant to the application of authoritative guidance issued by the Financial Accounting Standards Board ("FASB") to the Company's lease of office and laboratory facilities in Tarrytown, New York, the Company recognized a facility lease obligation of $92.6 million and $7.7 million during the nine months ended September 30, 2014 and 2013, respectively, in connection with capitalizing, on the Company's books, the landlord's costs of constructing new facilities that the Company has leased. In addition, included in property, plant, and equipment at September 30, 2014 and September 30, 2013 were $4.5 million and $1.0 million of capitalized interest for the nine months ended September 30, 2014 and September 30, 2013, respectively, as the related facilities are currently under construction.

Legal Matters (Notes)	9 Months Ended
Legal Matters (Notes)	Sep. 30, 2014
Commitments and Contingencies Disclosure [Abstract]
Legal Matters	Legal Matters From time to time, the Company is a party to legal proceedings in the course of the Company's business. Costs associated with the Company's involvement in legal proceedings are expensed as incurred. Proceedings Relating to ‘287 Patent and '018 Patent The Company is a party to patent infringement litigation involving its European Patent No. 1,360,287 (the "'287 Patent") and its U.S. Patent No. 8,502,018 (the "'018 Patent"), both of which concern genetically altered mice capable of producing chimeric antibodies that are part human and part mouse. Chimeric antibody sequences can be used to produce high-affinity fully human monoclonal antibodies. In these proceedings (the "'287 Patent Infringement Litigation" and "'018 Patent Infringement Litigation," respectively), the Company claims infringement of several claims of the '287 Patent and the '018 Patent (as applicable), and seeks, among other types of relief, an injunction and an account of profits in connection with the defendants' infringing acts, which may include, among other things, the making, use, keeping, sale, or offer for sale of genetically engineered mice (or certain cells from which they are derived) that infringe one or more claims of the '287 Patent and the '018 Patent (as applicable). With respect to the '018 Patent Infringement Litigation against Ablexis, LLC, on October 31, 2014, the Company and Ablexis reached a confidential settlement and filed a joint stipulation dismissing the action with prejudice. As the '287 Patent Infringement Litigation and remaining '018 Patent Infringement Litigation proceedings are at an early stage, at this time the Company is not able to predict the outcome of, or an estimate of gain, if any, related to, these proceedings. Proceedings Relating to PCSK9 Antibody (Alirocumab) On October 17, 2014 and October 28, 2014, Amgen Inc. filed lawsuits against Regeneron, Sanofi, Aventisub LLC, and Aventis Pharmaceuticals, Inc. in the United States District Court for the District of Delaware seeking an injunction to prevent Regeneron and the other defendants from making, using, offering to sell, or selling within the United States (as well as importing into the United States) alirocumab, the antibody to PCSK9 for LDL cholesterol reduction Regeneron is jointly developing with Sanofi. In the complaints, Amgen asserts U.S. Patent Nos. 8,563,698, 8,829,165, and 8,859,741 and U.S. Patent Nos. 8,871,913 and 8,871,914, respectively. Amgen also seeks a judgment of patent infringement of the asserted patents, monetary damages (together with interest), costs and expenses of the lawsuits, and attorneys’ fees. This matter has not yet progressed sufficiently through discovery and/or development of important factual information and legal issues to enable the Company to estimate a range of possible loss, if any.

Recently Issued Accounting Standards (Notes)	9 Months Ended
Recently Issued Accounting Standards (Notes)	Sep. 30, 2014
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Description of New Accounting Pronouncements Not yet Adopted [Text Block]	Recently Issued Accounting Standards In May 2014, the FASB issued a new standard related to revenue recognition, Revenue from Contracts with Customers, which will replace existing revenue recognition guidance. The new standard requires an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers. To achieve that core principle, an entity must identify the contract(s) with a customer, identify the performance obligations in the contract, determine the transaction price, allocate the transaction price to the performance obligations in the contract, and recognize revenue when (or as) the entity satisfies the performance obligation. The new standard will be effective for annual and interim reporting periods beginning after December 15, 2016, and early adoption is not permitted. The standard allows for two transition methods - retrospectively to each prior reporting period presented or retrospectively with the cumulative effect of initially applying the standard recognized at the date of initial adoption. The Company has not yet determined its method of transition and is evaluating the impact that this guidance will have on the Company's financial statements.

Net Product Sales (Policies)	9 Months Ended
Net Product Sales (Policies)	Sep. 30, 2014
Revenues [Abstract]
Revenue Recognition, Revenue Reductions [Policy Text Block]	Revenue from product sales is recorded net of applicable provisions for rebates and chargebacks under governmental programs, distribution-related fees, prompt pay discounts, and other sales-related deductions.

Legal Matters (Policies)	9 Months Ended
Legal Matters (Policies)	Sep. 30, 2014
Commitments and Contingencies Disclosure [Abstract]
Legal Costs, Policy [Policy Text Block]	Costs associated with the Company's involvement in legal proceedings are expensed as incurred.

Net Product Sales (Tables)

9 Months Ended

Sep. 30, 2014

Revenues [Abstract]

Sales Related Deductions Activity

The following table summarizes the provisions, and credits/payments, for these sales-related deductions during the nine months ended September 30, 2014.



	Rebates & Chargebacks			Distribution- Related Fees			Other Sales- Related Deductions			Total
Balance as of December 31, 2013	$	4,400		$	19,663		$	538		$	24,601
Provision related to current period sales	23,265			53,689			1,202			78,156
Credits/payments	(23,873		)	(54,878		)	(1,211		)	(79,962		)
Balance as of September 30, 2014	$	3,792		$	18,474		$	529		$	22,795

Collaboration Agreements (Tables)

9 Months Ended

Sep. 30, 2014

Collaboration Agreement [Abstract]

Collaboration revenue with related party



	Three months ended September 30,
Sanofi Collaboration Revenue	2014			2013
ZALTRAP:
Regeneron's share of losses in connection with commercialization of ZALTRAP	$	(1,008	)	$	(6,575	)
Reimbursement of Regeneron research and development expenses	1,261			1,316
Other	756			2,625
Total ZALTRAP	1,009			(2,634		)
Antibody:
Reimbursement of Regeneron research and development expenses	140,497			133,128
Regeneron's share of commercialization expenses	(12,830		)	—
Other	4,249			3,865
Total Antibody	131,916			136,993
Total Sanofi collaboration revenue	$	132,925		$	134,359



	Nine months ended September 30,
Sanofi Collaboration Revenue	2014			2013
ZALTRAP:
Regeneron's share of losses in connection with commercialization of ZALTRAP	$	(4,912	)	$	(22,581	)
Reimbursement of Regeneron research and development expenses	3,691			5,497
Other	4,417			6,610
Total ZALTRAP	3,196			(10,474		)
Antibody:
Reimbursement of Regeneron research and development expenses	405,212			338,027
Regeneron's share of commercialization expenses	(17,125		)	—
Up-front payments to Sanofi for acquisition of rights related to two antibodies	—			(20,000		)
Other	14,745			11,608
Total Antibody	402,832			329,635
Total Sanofi collaboration revenue	$	406,028		$	319,161

Collaboration revenue

The collaboration revenue the Company earned from Bayer HealthCare is detailed below:



	Three months ended September 30,
Bayer HealthCare Collaboration Revenue	2014		2013
EYLEA:
Regeneron's net profit in connection with commercialization of EYLEA outside the United States	$	85,351	$	31,769
Sales and substantive development milestones	30,000		45,000
Cost-sharing of Regeneron EYLEA development expenses	4,394		3,739
Other	12,745		8,075
Total EYLEA	132,490		88,583
PDGFR-beta antibody:
Cost-sharing of REGN2176-3 development expenses	518		—
Other	2,845		—
Total PDGFR-beta	3,363		—
Total Bayer HealthCare collaboration revenue	$	135,853	$	88,583



	Nine months ended September 30,
Bayer HealthCare Collaboration Revenue	2014		2013
EYLEA:
Regeneron's net profit in connection with commercialization of EYLEA outside the United States	$	213,291	$	57,186
Sales and substantive development milestones	75,000		45,000
Cost-sharing of Regeneron EYLEA development expenses	26,235		13,207
Other	34,490		19,201
Total EYLEA	349,016		134,594
PDGFR-beta antibody:
Cost-sharing of REGN2176-3 development expenses	1,657		—
Other	7,787		—
Total PDGFR-beta	9,444		—
Total Bayer HealthCare collaboration revenue	$	358,460	$	134,594

Net Income Per Share (Tables)

9 Months Ended

Sep. 30, 2014

Earnings Per Share [Abstract]

Basic and Diluted Net Income (Loss) Per Share

The calculations of basic and diluted net income per share are as follows:



	Three months ended September 30,
	2014		2013
Net income - basic	$	79,720	$	141,306
Effective of dilutive securities:
Convertible senior notes - interest expense related to contractual coupon interest rate and amortization of discount and note issuance costs	2,803		4,678
Net income - diluted	$	82,523	$	145,984

(Shares in thousands)
Weighted average shares - basic	100,796		98,226
Effect of dilutive securities:
Stock options	9,377		10,379
Restricted stock	430		462
Convertible senior notes	4,033		4,761
Warrants	2,787		2,885
Dilutive potential shares	16,627		18,487
Weighted average shares - diluted	117,423		116,713

Net income per share - basic	$	0.79	$	1.44
Net income per share - diluted	$	0.70	$	1.25



	Nine months ended September 30,
	2014		2013
Net income - basic	$	237,898	$	327,556
Effective of dilutive securities:
Convertible senior notes - interest expense related to contractual coupon interest rate and amortization of discount and note issuance costs	—		13,857
Net income - diluted	$	237,898	$	341,413

(Shares in thousands)
Weighted average shares - basic	100,325		97,602
Effect of dilutive securities:
Stock options	9,515		10,220
Restricted stock	413		415
Convertible senior notes	—		4,761
Warrants	2,950		2,556
Dilutive potential shares	12,878		17,952
Weighted average shares - diluted	113,203		115,554

Net income per share - basic	$	2.37	$	3.36
Net income per share - diluted	$	2.10	$	2.95

Antidilutive Securities

Shares which have been excluded from the September 30, 2014 and 2013 diluted per share amounts because their effect would have been antidilutive include the following:

Marketable Securities (Tables)

9 Months Ended

Sep. 30, 2014

Investments, Debt and Equity Securities [Abstract]

Available-for-sale Securities

The following tables summarize the Company's investments in marketable securities at September 30, 2014 and December 31, 2013.



	Amortized		Unrealized					Fair
At September 30, 2014	Cost Basis		Gains		Losses			Value
Unrestricted
U.S. government and government agency obligations	$	51,059	$	71	$	(1	)	$	51,129
Corporate bonds	696,149		574		(1,131		)	695,592
Municipal bonds	42,756		94		(8		)	42,842
Equity securities	1,166		3,933		—			5,099
	791,130		4,672		(1,140		)	794,662
Restricted
Equity securities	15,000		39,431		—			54,431
	$	806,130	$	44,103	$	(1,140	)	$	849,093

At December 31, 2013
Unrestricted
U.S. government and government agency obligations	$	107,493	$	55	$	(27	)	$	107,521
Corporate bonds	369,321		233		(361		)	369,193
Commercial paper	23,891		53		—			23,944
Municipal bonds	36,935		45		(59		)	36,921
International government agency obligations	2,007		1		—			2,008
Certificates of deposit	7,509		5		—			7,514
Equity securities	1,166		—		—			1,166
	$	548,322	$	392	$	(447	)	$	548,267

Marketable Securities, Based on Contractual Maturity Dates

The fair values of debt security investments by contractual maturity as of September 30, 2014 and December 31, 2013 consist of the following:



	September 30, 2014		December 31, 2013
Maturities within one year	$	287,739	$	158,376
Maturities after one year through five years	496,700		383,410
Maturities after five years through ten years	5,124		4,138
Maturities after ten years	—		1,177
	$	789,563	$	547,101

Fair Value and Unrealized Losses of Marketable Securities



	Less than 12 Months					12 Months or Greater		Total
At September 30, 2014	Fair Value		Unrealized Loss			Fair Value	Unrealized Loss	Fair Value		Unrealized Loss
U.S. government and government agency obligations	$	1,401	$	(1	)	—	—	$	1,401	$	(1	)
Corporate bonds	343,835		(1,131		)	—	—	343,835		(1,131		)
Municipal bonds	10,502		(8		)	—	—	10,502		(8		)
	$	355,738	$	(1,140	)	—	—	$	355,738	$	(1,140	)

At December 31, 2013
U.S. government and government agency obligations	$	49,241	$	(27	)	—	—	$	49,241	$	(27	)
Corporate bonds	176,140		(361		)	—	—	176,140		(361		)
Municipal bonds	14,431		(59		)	—	—	14,431		(59		)
	$	239,812	$	(447	)	—	—	$	239,812	$	(447	)

Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2014

Fair Value Disclosures [Abstract]

Schedule of assets measured at fair value on a recurring basis

The Company’s assets that are measured at fair value on a recurring basis, at September 30, 2014 and December 31, 2013, consist of the following:



			Fair Value Measurements at Reporting Date Using
At September 30, 2014	Fair Value		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)
Available-for-sale marketable securities:
Unrestricted
U.S. government and government agency obligations	$	51,129	—		$	51,129
Corporate bonds	695,592		—		695,592
Municipal bonds	42,842		—		42,842
Equity securities	5,099		$	5,099	—
	794,662		5,099		789,563
Restricted
Equity securities	54,431		—		54,431
	$	849,093	$	5,099	$	843,994

At December 31, 2013
Available-for-sale marketable securities:
Unrestricted
U.S. government and government agency obligations	$	107,521	—		$	107,521
Corporate bonds	369,193		—		369,193
Commercial paper	23,944		—		23,944
Municipal bonds	36,921		—		36,921
International government agency obligations	2,008		—		2,008
Certificates of deposit	7,514		—		7,514
Equity securities	1,166		$	1,166	—
	$	548,267	$	1,166	$	547,101

Inventory (Tables)

9 Months Ended

Sep. 30, 2014

Inventory Disclosure [Abstract]

Schedule of Inventory, Current

Inventories consist of the following:



	September 30,		December 31,
	2014		2013
Raw materials	$	10,170	$	9,120
Work-in-process	70,965		35,868
Finished goods	11,368		14,352
Deferred costs	27,814		11,014
	$	120,317	$	70,354

Accounts Payable and Accrued Expenses (Tables)

9 Months Ended

Sep. 30, 2014

Payables and Accruals [Abstract]

Schedule of Accounts Payable and Accrued Liabilities

Accounts payable and accrued expenses consist of the following:



	September 30,		December 31,
	2014		2013
Accounts payable	$	47,342	$	61,936
Accrued payroll and related costs	75,159		69,429
Accrued clinical trial expense	45,384		23,654
Accrued sales-related charges, deductions, and royalties	114,408		66,855
Other accrued expenses and liabilities	55,683		29,022
	$	337,976	$	250,896

Net Product Sales (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
Net Product Sales (Details) - USD ($) $ in Thousands	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Revenue Disclosure [Line Items]
Branded Prescription Drug Fee	$ 40,600
Net product sales	448,844	$ 367,118	$ 1,229,244	$ 1,019,751
Activity of Sales Related Deductions [Roll Forward]
Balance	22,795		22,795		$ 24,601
Provision related to current period sales			78,156
Credits/payments			(79,962)
Rebates and Chargebacks
Activity of Sales Related Deductions [Roll Forward]
Balance	3,792		3,792		4,400
Provision related to current period sales			23,265
Credits/payments			(23,873)
Distribution Related Fees
Activity of Sales Related Deductions [Roll Forward]
Balance	18,474		18,474		19,663
Provision related to current period sales			53,689
Credits/payments			(54,878)
Other Sales Related Deductions
Activity of Sales Related Deductions [Roll Forward]
Balance	$ 529		529		$ 538
Provision related to current period sales			1,202
Credits/payments			$ (1,211)
Customer concentration risk \| Gross Sales Revenue
Risks and Uncertainties [Abstract]
Concentration risk, percentage	72.00%	75.00%	75.00%	76.00%
EYLEA
Revenue Disclosure [Line Items]
Net product sales	$ 445,000	$ 363,100	$ 1,218,800	$ 1,006,800
ARCALYST
Revenue Disclosure [Line Items]
Net product sales	$ 3,800	$ 4,000	$ 10,400	$ 12,900

Collaboration Agreements (Sanofi) (Details) $ in Thousands	1 Months Ended	3 Months Ended				9 Months Ended
Collaboration Agreements (Sanofi) (Details) $ in Thousands	Jul. 31, 2014 USD ($)	Sep. 30, 2014 USD ($)	Mar. 31, 2014 USD ($)	Sep. 30, 2013 USD ($)	Jun. 30, 2013 USD ($)	Sep. 30, 2014 USD ($)	Sep. 30, 2013 USD ($) family
Collaboration Agreement [Line Items]
Research and development		$ 337,728		$ 224,045		$ 919,608	$ 591,807
Revenue from Related Parties		132,925		134,359		406,028	319,161
ZALTRAP Agreement
Collaboration Agreement [Line Items]
Net profit (loss) from commercialization of products under collaboration agreement		(1,008)		(6,575)		(4,912)	(22,581)
Reimbursement of Regeneron research and development expenses		1,261		1,316		3,691	5,497
Contracts Revenue		756		2,625		4,417	6,610
Revenue from Related Parties		1,009		(2,634)		3,196	(10,474)
Ang2
Collaboration Agreement [Line Items]
Research and Development Asset Acquired Other than Through Business Combination, Written-off					$ 10,000		10,000
Antibody Collaboration
Collaboration Agreement [Line Items]
Net profit (loss) from commercialization of products under collaboration agreement		(12,830)		0		(17,125)	$ 0
Number of Payments the Company made							2
Research and Development Asset Acquired Other than Through Business Combination, Written-off						$ 0	$ 20,000
Number of families of novel antibodies \| family							2
Percentage of Trial Costs borne by collaborating party						80.00%
Percentage of Trial Costs borne by entity						20.00%
Research and development		28,400				$ 81,300
Reimbursement of Regeneron research and development expenses		140,497		133,128		405,212	$ 338,027
Contracts Revenue		4,249		3,865		14,745	11,608
Revenue from Related Parties		131,916		$ 136,993		402,832	329,635
Payments for Purchase of Other Assets	$ 67,500
PDGF
Collaboration Agreement [Line Items]
Number of Payments the Company made			2
Research and Development Asset Acquired Other than Through Business Combination, Written-off					$ 10,000		$ 10,000
Other Research and Development Expense			$ 5,000
Milestone payment						$ 30,000
Sanofi [Member]
Collaboration Agreement [Line Items]
Research and Development Asset Acquired Other than Through Business Combination, Written-off		$ 33,750

Collaboration Agreements (Bayer HealthCare LLC) (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Collaboration Agreement [Line Items]
Other Collaboration Revenue	$ 135,853,000	$ 88,583,000	$ 358,460,000	$ 134,594,000
EYLEA
Collaboration Agreement [Line Items]
Net profit (loss) from commercialization of products under collaboration agreement	85,351,000	31,769,000	213,291,000	57,186,000
Revenue Recognition, Milestone Method, Revenue Recognized	30,000,000	45,000,000	75,000,000	45,000,000
Reimbursement of Regeneron research and development expenses	4,394,000	3,739,000	26,235,000	13,207,000
Contracts Revenue	12,745,000	8,075,000	34,490,000	19,201,000
Other Collaboration Revenue	132,490,000	88,583,000	349,016,000	134,594,000
PDGFR-beta
Collaboration Agreement [Line Items]
Reimbursement of Regeneron research and development expenses	518,000	0	1,657,000	0
Recognition of Deferred Revenue	2,845,000	0	7,787,000	0
Other Collaboration Revenue	$ 3,363,000	$ 0	$ 9,444,000	$ 0

Collaboration Agreements (EYLEA) (Details) $ in Millions	3 Months Ended			9 Months Ended
Collaboration Agreements (EYLEA) (Details) $ in Millions	Sep. 30, 2014 USD ($)	Jun. 30, 2014 USD ($)	Mar. 31, 2014 USD ($)	Sep. 30, 2014 USD ($)
Collaboration Agreement [Line Items]
Number of sales milestone payments the Company received	2			5
Levels of twelve month sales at which sales milestone payments were received - 500 million				$ 500.0
Levels of twelve month sales at which sales milestone payments were received - 600 million				600.0
Levels of twelve month sales at which sales milestone payments were received - 700 million				$ 700.0
Levels of twelve month sales at which sales milestone payments were received - 800 million	$ 800.0
Levels of twelve month sales at which sales milestone payments were received - 900 million	900.0
Period for Achieving Sales Target for Milestone Payment, Rolling Basis				12 months
levels of twelve months sales at which sales milestone payments maybe received - 1 billion				$ 1,000.0
levels of twelve month sales at which sales milestone payments maybe received - 200 million				$ 200.0
sales achievement - $500 million
Collaboration Agreement [Line Items]
Revenue Recognition, Milestone Method, Revenue Recognized			$ 15.0
sales achievement - $600 million
Collaboration Agreement [Line Items]
Revenue Recognition, Milestone Method, Revenue Recognized			15.0
sales achievement - 700 million
Collaboration Agreement [Line Items]
Revenue Recognition, Milestone Method, Revenue Recognized		$ 15.0
sales achievement - $800 million
Collaboration Agreement [Line Items]
Revenue Recognition, Milestone Method, Revenue Recognized	15.0
sales achievement - $900 million
Collaboration Agreement [Line Items]
Revenue Recognition, Milestone Method, Revenue Recognized	$ 15.0
sales achievement - $1 billion
Collaboration Agreement [Line Items]
Number of sales milestone payments the Company might receive				1
Maximum amount of sales milestone payments if total sales achieve specific levels				$ 15.0
sales achievement - $200 million
Collaboration Agreement [Line Items]
Maximum amount of sales milestone payments if total sales achieve specific levels				$ 30.0
BRVO
Collaboration Agreement [Line Items]
Reimbursement of Regeneron research and development expenses			$ 15.7

Collaboration Agreements (PDGFR-beta Antibody) (Details) - PDGF	3 Months Ended	9 Months Ended
	Mar. 31, 2014 USD ($)	Sep. 30, 2014 USD ($)
Collaboration Agreement [Line Items]
Amount of non refundable payment received for collaboration agreement		$ 25,500,000.00
Percentage of global development cost to be paid by the collaboration partner under the collaboration		25.00%
Percentage of development cost for the territory outside the United States to be paid for under the collaboration		50.00%
Percentage of development milestone payments to be reimbursed		50.00%
Number of development milestone payments the Company received	2
Deferred Revenue, Additions	$ 2,500,000	$ 25,500,000
Future development milestone payment		15,000,000
Opt in payment		20,000,000
Amount of milestone payment that may be received relating to marketing approval		$ 20,000,000

Collaboration Agreements (Avalanche Biotechnologies, Inc.) (Details) $ in Thousands	1 Months Ended	7 Months Ended	9 Months Ended
	Jul. 31, 2014 shares	Jul. 31, 2014 USD ($)	Sep. 30, 2014 USD ($)	Sep. 30, 2013 USD ($)
Collaboration Agreement [Line Items]
Payments to Acquire Marketable Securities			$ 478,436	$ 477,312
Collaboration Agreement with Avalanche Biotechnologies, inc.
Collaboration Agreement [Line Items]
Research and Development Asset Acquired Other than Through Business Combination, Written-off			2,000
Pre-payment of collaboration research costs			6,000
Potential future milestone payments			$ 640,000
Number of therapeutic targets			8
Payment to acquire preferred share of non-public entity			$ 5,000
Number of therapeutic targets of Avalanche's choice			2
Payments to Acquire Marketable Securities		$ 10,000
Number of shares of Common Stock to be purchased \| shares	588,235
Per Product \| Collaboration Agreement with Avalanche Biotechnologies, inc.
Collaboration Agreement [Line Items]
Potential future milestone payments			$ 80,000

Net Income Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Earnings Per Share [Abstract]
Net income	$ 79,720,000	$ 141,306,000	$ 237,898,000	$ 327,556,000
Interest on Convertible Debt, Net of Tax	2,803,000	4,678,000	0	13,857,000
Net Income (Loss) Available to Common Stockholders, Diluted	$ 82,523,000	$ 145,984,000	$ 237,898,000	$ 341,413,000
Weighted Average Number of Shares Outstanding Reconciliation [Abstract]
Weighted average shares outstanding - basic	100,796	98,226	100,325	97,602
Effect of dilutive securities (in shares):
Stock options	9,377	10,379	9,515	10,220
Restricted stock	430	462	413	415
Incremental Common Shares Attributable to Dilutive Effect of Conversion of Debt Securities	4,033	4,761	0	4,761
Warrants	2,787	2,885	2,950	2,556
Dilutive potential shares	16,627	18,487	12,878	17,952
Weighted average shares - diluted (in shares)	117,423	116,713	113,203	115,554
Earnings Per Share, Basic and Diluted [Abstract]
Net income per share - basic	$ 0.79	$ 1.44	$ 2.37	$ 3.36
Net income per share - diluted (in dollars per share)	$ 0.70	$ 1.25	$ 2.10	$ 2.95
Stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Weighted average number of shares	1,227	135	3,741	1,265
Convertible senior notes
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Weighted average number of shares			4,483	0

Marketable Securities (Details) - USD ($)	3 Months Ended	9 Months Ended		12 Months Ended
Marketable Securities (Details) - USD ($)	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Gross Realized Gains	$ 500,000		$ 1,000,000
Available for sale securities, realized loss	$ 0		$ 0
Amortized Cost Basis		$ 806,130,000		$ 548,322,000
Unrealized Gains		44,103,000		392,000
Unrealized (Losses)		(1,140,000)		(447,000)
Total fair value of available-for-sale marketable securities		849,093,000		548,267,000
Available-for-sale Securities, Debt Maturities, Fair Value [Abstract]
Maturities within one year		287,739,000		158,376,000
Maturities after one year through five years		496,700,000		383,410,000
Maturities after five years through ten years		5,124,000		4,138,000
Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value		0		1,177,000
Total		789,563,000		547,101,000
Continuous Unrealized Loss Position, Fair Value [Abstract]
Fair Value - Less than 12 Months		355,738,000		239,812,000
Fair Value - 12 Months or Greater		0		0
Fair Value - Total		355,738,000		239,812,000
Continuous Unrealized Loss Position, Aggregate Losses [Abstract]
Unrealized Loss - Less than 12 months		(1,140,000)		(447,000)
Unrealized Loss - 12 Months or Greater		0		0
Unrealized Loss - Total		(1,140,000)		(447,000)
U.S. government and government agency obligations
Continuous Unrealized Loss Position, Fair Value [Abstract]
Fair Value - Less than 12 Months		1,401,000		49,241,000
Fair Value - Total		1,401,000		49,241,000
Continuous Unrealized Loss Position, Aggregate Losses [Abstract]
Unrealized Loss - Less than 12 months		(1,000)		(27,000)
Unrealized Loss - Total		(1,000)		(27,000)
Corporate bonds
Continuous Unrealized Loss Position, Fair Value [Abstract]
Fair Value - Less than 12 Months		343,835,000		176,140,000
Fair Value - Total		343,835,000		176,140,000
Continuous Unrealized Loss Position, Aggregate Losses [Abstract]
Unrealized Loss - Less than 12 months		(1,131,000)		(361,000)
Unrealized Loss - Total		(1,131,000)		(361,000)
Municipal bonds
Continuous Unrealized Loss Position, Fair Value [Abstract]
Fair Value - Less than 12 Months		10,502,000		14,431,000
Fair Value - Total		10,502,000		14,431,000
Continuous Unrealized Loss Position, Aggregate Losses [Abstract]
Unrealized Loss - Less than 12 months		(8,000)		(59,000)
Unrealized Loss - Total		(8,000)		(59,000)
Unrestricted [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost Basis		791,130,000
Unrealized Gains		4,672,000
Unrealized (Losses)		(1,140,000)
Total fair value of available-for-sale marketable securities		794,662,000
Unrestricted [Member] \| U.S. government and government agency obligations
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost Basis		51,059,000		107,493,000
Unrealized Gains		71,000		55,000
Unrealized (Losses)		(1,000)		(27,000)
Total fair value of available-for-sale marketable securities		51,129,000		107,521,000
Unrestricted [Member] \| Corporate bonds
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost Basis		696,149,000		369,321,000
Unrealized Gains		574,000		233,000
Unrealized (Losses)		(1,131,000)		(361,000)
Total fair value of available-for-sale marketable securities		695,592,000		369,193,000
Unrestricted [Member] \| Commercial Paper
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost Basis				23,891,000
Unrealized Gains				53,000
Unrealized (Losses)				0
Total fair value of available-for-sale marketable securities				23,944,000
Unrestricted [Member] \| Municipal bonds
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost Basis		42,756,000		36,935,000
Unrealized Gains		94,000		45,000
Unrealized (Losses)		(8,000)		(59,000)
Total fair value of available-for-sale marketable securities		42,842,000		36,921,000
Unrestricted [Member] \| International government agency obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost Basis				2,007,000
Unrealized Gains				1,000
Unrealized (Losses)				0
Total fair value of available-for-sale marketable securities				2,008,000
Unrestricted [Member] \| Certificates of Deposit
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost Basis				7,509,000
Unrealized Gains				5,000
Unrealized (Losses)				0
Total fair value of available-for-sale marketable securities				7,514,000
Unrestricted [Member] \| Equity Securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost Basis		1,166,000		1,166,000
Unrealized Gains		3,933,000		0
Unrealized (Losses)		0		0
Total fair value of available-for-sale marketable securities		5,099,000		$ 1,166,000
Restricted [Member] \| Equity Securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost Basis		15,000,000
Unrealized Gains		39,431,000
Unrealized (Losses)		0
Total fair value of available-for-sale marketable securities		$ 54,431,000

Fair Value Measurements (Details) - USD ($)	3 Months Ended		9 Months Ended
Fair Value Measurements (Details) - USD ($)	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Instrument, Face Amount					$ 400,000,000
Available-for-sale marketable securities:
Total fair value of available-for-sale marketable securities	$ 849,093,000		$ 849,093,000		548,267,000
Convertible senior notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Instrument, Face Amount	$ 338,900,000		$ 338,900,000		$ 400,000,000
Convertible Debt [Abstract]
Interest rate, stated percentage	1.875%		1.875%		1.875%
Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other than Temporary Impairment Losses, Investments	$ 0	$ 0	$ 0	$ 0
Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable Securities, Unrealized Gain (Loss)	0	$ 0	0	$ 0
Measured on a recurring basis \| Fair Value
Available-for-sale marketable securities:
Total fair value of available-for-sale marketable securities	849,093,000		849,093,000		$ 548,267,000
Measured on a recurring basis \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Available-for-sale marketable securities:
Total fair value of available-for-sale marketable securities	5,099,000		5,099,000		1,166,000
Measured on a recurring basis \| Significant Other Observable Inputs (Level 2)
Available-for-sale marketable securities:
Total fair value of available-for-sale marketable securities	843,994,000		843,994,000		547,101,000
Convertible Debt [Abstract]
Fair value of the outstanding notes	1,433,800,000		1,433,800,000		1,327,200,000
Restricted [Member] \| Measured on a recurring basis \| Fair Value
Available-for-sale marketable securities:
Equity securities	54,431,000		54,431,000
Restricted [Member] \| Measured on a recurring basis \| Significant Other Observable Inputs (Level 2)
Available-for-sale marketable securities:
Equity securities	54,431,000		54,431,000
Unrestricted [Member]
Available-for-sale marketable securities:
Total fair value of available-for-sale marketable securities	794,662,000		794,662,000
Unrestricted [Member] \| Measured on a recurring basis \| Fair Value
Available-for-sale marketable securities:
U.S. government and government agency obligations	51,129,000		51,129,000		107,521,000
Corporate bonds	695,592,000		695,592,000		369,193,000
Municipal bonds	42,842,000		42,842,000		36,921,000
Commercial paper					23,944,000
International government agency obligations					2,008,000
Certificates of deposit					7,514,000
Equity securities	5,099,000		5,099,000		1,166,000
Total fair value of available-for-sale marketable securities	794,662,000		794,662,000
Unrestricted [Member] \| Measured on a recurring basis \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Available-for-sale marketable securities:
Equity securities	5,099,000		5,099,000		1,166,000
Total fair value of available-for-sale marketable securities	5,099,000		5,099,000
Unrestricted [Member] \| Measured on a recurring basis \| Significant Other Observable Inputs (Level 2)
Available-for-sale marketable securities:
U.S. government and government agency obligations	51,129,000		51,129,000		107,521,000
Corporate bonds	695,592,000		695,592,000		369,193,000
Municipal bonds	42,842,000		42,842,000		36,921,000
Commercial paper					23,944,000
International government agency obligations					2,008,000
Certificates of deposit					$ 7,514,000
Total fair value of available-for-sale marketable securities	$ 789,563,000		$ 789,563,000

Inventory (Schedule of Inventory) (Details) - USD ($) $ in Thousands	Sep. 30, 2014	Dec. 31, 2013
Inventory Disclosure [Abstract]
Raw materials	$ 10,170	$ 9,120
Work in process	70,965	35,868
Finished goods	11,368	14,352
Deferred costs	27,814	11,014
Total Inventories	$ 120,317	$ 70,354

Inventory (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Inventory (Narrative) (Details) - USD ($) $ in Millions	Sep. 30, 2014	Sep. 30, 2014	Sep. 30, 2013
Inventory Disclosure [Abstract]
Inventory write-downs and reserves	$ 1.6	$ 3.5	$ 4.8

Accounts Payable and Accrued Expenses (Details) - USD ($) $ in Thousands	Sep. 30, 2014	Dec. 31, 2013
Accounts Payable and Accrued Liabilities, Current [Abstract]
Accounts payable	$ 47,342	$ 61,936
Accrued payroll and related costs	75,159	69,429
Accrued clinical trial expense	45,384	23,654
Accrued sales-related charges, deductions and royalties	114,408	66,855
Other accrued expenses and liabilities	55,683	29,022
Accounts payable and accrued expenses	$ 337,976	$ 250,896

Convertible Debt (Details) $ in Thousands	1 Months Ended	3 Months Ended			6 Months Ended	9 Months Ended
Convertible Debt (Details) $ in Thousands	Oct. 31, 2014 USD ($)	Sep. 30, 2014 USD ($)	Mar. 31, 2014 shares	Sep. 30, 2013 USD ($)	Jun. 30, 2014 USD ($) shares	Sep. 30, 2014 USD ($)	Sep. 30, 2013 USD ($)	Dec. 31, 2013 USD ($)
Debt Conversion	$ 160,800				$ 61,100
Debt Instrument, Face Amount								$ 400,000
Repayments of Convertible Debt						$ 61,125	$ 0
Issuance of Common Stock in connection with conversion of convertible senior notes (in shares) \| shares					521,876
Gains (Losses) on Extinguishment of Debt		$ 0		$ 0		(10,787)	0
Stock Issued During Period, Shares, Acquisitions \| shares					521,876
Payments for Repurchase of Warrants					$ 143,041	143,041	$ 0
Maximum number of shares issuable upon exercise of warrants \| shares			4,760,840		4,033,324
Adjustments to Additional Paid in Capital, Equity Component of Convertible Debt, Subsequent Adjustments						156,657
Convertible senior notes
Trading days to calculate settlement			40
Debt Instrument, Face Amount		$ 338,900				$ 338,900		$ 400,000

Income Taxes (Details) - USD ($)	3 Months Ended		9 Months Ended
Income Taxes (Details) - USD ($)	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Operating Loss Carryforwards [Line Items]
Total income tax expense (benefit)	$ 96,358,000	$ 84,378,000	$ 316,562,000	$ 187,651,000
Effective income tax rate	54.70%	37.40%	57.10%	36.40%
Effective Income Tax Rate Reconciliation, Change in Tax Rates, Percent			2.20%
Effective Income Tax Rate Reconciliation, Tax Credit, Research, Percent				4.30%
Available-for-sale Securities, Income Tax Expense on Change in Unrealized Holding Gain (Loss)	$ 13,500,000	$ 0	$ 14,900,000	$ 0
State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Effective income tax rate			0.00%

Statement of Cash Flows (Details) - USD ($) $ in Millions	9 Months Ended
Statement of Cash Flows (Details) - USD ($) $ in Millions	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013	Dec. 31, 2012
Interest Costs Capitalized	$ 4.5	$ 1.0
Accrued capital expenditures	38.6	18.4	$ 16.1	$ 8.6
Facility lease obligation recognized during the period	$ 92.6	$ 7.7