CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Cash flows from operating activities:
Net income	$ 377,603	$ 270,664
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation and amortization	48,006	31,325
Non-cash compensation expense	273,941	198,016
Other non-cash charges and expenses, net	7,795	33,017
Deferred taxes	(162,652)	(59,069)
Changes in assets and liabilites
Increase in Sanofi, Bayer, and trade accounts receivable	(284,178)	(418,753)
Increase in Inventories	(72,888)	(45,591)
Decrease in prepaid expenses and other assets	57,086	33,842
Increase (decrease) in deferred revenue	65,850	(16,685)
Increase in accounts payable, accrued expenses and other liabilities	133,925	129,338
Total adjustments	66,885	(114,560)
Net cash provided by (used in) operating activities	444,488	156,104
Cash flows from investing activities:
Purchases of marketable securities	(228,942)	(340,844)
Sales or maturities of marketable securities	102,177	193,769
Capital expenditures	(242,930)	(354,055)
Net cash used in investing activities	(369,695)	(501,130)
Cash flows from financing activities:
(Payments) proceeds in connection with facility lease obligations	(1,213)	26,780
Repayments of convertible senior notes	(12,650)	(144,001)
Payments in connection with deduction of outstanding warrants	(242,117)	(124,531)
Proceeds from issuance of Common Stock	63,606	115,825
Payments in connection with Common Stock tendered for employee tax obligations	(45,013)	(35,930)
Excess tax benefit from stock-based compensation	0	248,718
Net cash (used in) provided by financing activities	(237,387)	86,861
Net decrease in cash and cash equivalents	(162,594)	(258,165)
Cash and cash equivalents at beginning of period	809,102	648,719
Cash and cash equivalents at end of period	$ 646,508	$ 390,554