CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
CASH FLOWS FROM OPERATING ACTIVITIES [Abstract]
Net loss	$ (28,161)	$ (10,233)	$ (23,909)
Adjustments to reconcile net loss to net cash provided by operating activities
Depreciation and amortization	32,309	35,460	45,125
Amortization of investment premiums, net	0	0	1,219
Excess tax benefits for share-based compensation	(200)	(416)	(1,409)
Share-based compensation	8,771	9,910	11,148
Unrealized gain on hedging instruments	(826)	0	0
Unrealized gain on investments	(211)	0	0
Realized loss (gain) on debt and equity investments	2,717	(970)	(204)
Other-than-temporary impairment on securities	2,121	5,617	1,121
Provision for note receivable	2,151	0	0
Deferred tax assets	415	(73)	1,358
Amortization of debt offering costs	408	841	1,207
Gain from repurchase of convertible notes	0	(6,297)	(17,447)
Loss (gain) on disposal of property and equipment	342	784	(231)
Impairment of property and equipment	1,710	348	0
Changes in operating assets and liabilities [Abstract]
Accounts receivable, net	8,260	12,599	(2,207)
Inventories	6,522	5,117	(3,157)
Prepaid expenses and other assets	3,297	10,802	4,115
Accounts payable and accrued liabilities	(448)	(12,801)	(5,374)
Deferred revenue	(1,740)	(2,881)	(1,349)
Other long-term liabilities	1,900	168	(677)
Net cash provided by operating activities	39,337	47,975	9,329
CASH FLOWS FROM INVESTING ACTIVITIES [Abstract]
Capital expenditures	(5,779)	(7,726)	(10,249)
Purchases of available-for-sale securities	(86,252)	(453,138)	(381,560)
Proceeds from sales of available-for-sale securities	189,440	417,981	261,029
Proceeds from maturities of available-for-sale securities	32,982	110,477	124,090
Proceeds from sale of property and equipment	493	0	0
Purchase of technology rights	(3,250)	(1,383)	(500)
Net cash provided by (used in) investing activities	127,634	66,211	(7,190)
CASH FLOWS FROM FINANCING ACTIVITIES [Abstract]
Issuance of common stock, net	(683)	(1,182)	(813)
Repurchase of convertible notes	(3)	(143,993)	(50,669)
Excess tax benefits for share-based compensation	200	416	1,409
Net cash used in financing activities	(486)	(144,759)	(50,073)
Effect of exchange rate changes on cash and cash equivalents	(32)	415	284
Net increase (decrease) in cash and cash equivalents	166,453	(30,158)	(47,650)
Cash and cash equivalents at beginning of year	35,484	65,642	113,292
Cash and cash equivalents at end of year	201,937	35,484	65,642
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION [Abstract]
Cash paid for interest	3,341	9,284	9,963
Cash paid for income taxes	$ 633	$ 1,450	$ 144