Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Cash flows from operating activities:
Net income	$ 174,560	$ 304,442	$ 217,868
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	31,259	27,145	20,535
Provisions for inventory obsolescence	2,590	11,829	5,180
Share-based compensation expense (benefit)	320,786	30,115	(15,715)
Impairment write downs		6,804
Expense associated with outstanding license fees			37,049
Amortization of debt discount and debt issue costs	12,601	11,064	19,359
Current and deferred tax expense	104,343	136,229	81,432
Amortization of discount or premium on investments	4,501	4,604	4,474
Excess tax benefits from share-based compensation	(9,299)	(3,054)	(11,347)
Other	592	2,642	2,614
Changes in assets and liabilities:
Accounts receivable	(10,027)	(23,991)	(16,158)
Inventories	(12,394)	(5,933)	(16,055)
Other assets	(5,112)	(9,705)	(5,733)
Accounts payable and accrued expenses	7,507	(22,804)	20,251
Other liabilities	(196,640)	(145,759)	(93,559)
Net cash provided by operating activities	425,267	323,628	250,195
Cash flows from investing activities:
Purchases of property, plant and equipment	(31,910)	(111,905)	(35,978)
Purchases of held-to-maturity investments	(762,198)	(579,316)	(815,684)
Maturities of held-to-maturity investments	529,900	527,858	733,876
Investments in privately-owned companies	(30,766)
Acquisitions			(3,547)
Net cash used in investing activities	(294,974)	(163,363)	(121,333)
Cash flows from financing activities:
Principal payments of debt	(1,320)	(999)	(251,039)
Proceeds received from issuance of debt			250,000
Payments of transaction costs related to issuance of debt			(7,535)
Payment for convertible note hedge and warrants, net			(33,250)
Payments to repurchase common stock	(42,439)	(188,000)	(212,000)
Proceeds from exercise of stock options	26,611	16,805	24,398
Proceeds from employee stock purchase plan	2,734
Excess tax benefits from share-based compensation	9,299	3,054	11,347
Net cash (used in) provided by financing activities	(5,115)	(169,140)	(218,079)
Effect of exchange rate changes on cash and cash equivalents	(319)	229	(269)
Net (decrease) increase in cash and cash equivalents	124,859	(8,646)	(89,486)
Cash and cash equivalents, beginning of year	154,030	162,676	252,162
Cash and cash equivalents, end of year	278,889	154,030	162,676
Supplemental cash flow information:
Cash paid for interest	5,518	5,302	4,103
Cash paid for income taxes	142,140	101,505	46,510
Non-cash investing and financing activities:
Acquisitions-non-cash consideration			5,873
Non-cash additions to property, plant and equipment	9,018	1,820	23,063
Issuance of common stock upon conversion of convertible notes			27,294
Assumption of mortgage in connection with the acquisition of property			$ 3,736