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 loss	$ (16,327)	$ (10,696)	$ (28,161)
Adjustments to reconcile net loss to net cash provided by operating activities:
Depreciation and amortization	38,988	36,068	32,309
Amortization of inventory step-up in fair value	14,876	9,444	0
Excess tax benefits for share-based compensation	60	0	(200)
Share-based compensation	7,727	17,207	8,771
Deferred tax assets	(167)	(34,003)	415
Property and equipment, net—held for sale	0	3,491	1,710
Gain on sale of product line	(9,295)	0	0
Other non-cash transactions	5,423	1,348	6,702
Changes in operating assets and liabilities:
Accounts receivable, net	2,347	(514)	8,260
Inventories	2,455	12	6,522
Prepaid expenses and other assets	(9)	6,338	3,297
Accounts payable and accrued liabilities	(816)	(21,655)	(448)
Deferred revenue	9,596	(2,023)	(1,740)
Other long-term liabilities	(1,274)	(1,286)	1,900
Net cash provided by operating activities	53,584	3,731	39,337
CASH FLOWS FROM INVESTING ACTIVITIES:
Acquisition of businesses, net of cash acquired	0	(307,796)	0
Purchases of available-for-sale securities	0	0	(86,252)
Proceeds from sales of available-for-sale securities	9,364	52,063	189,440
Proceeds from maturities of available-for-sale securities	0	1,138	32,982
Proceeds from sale of property and equipment	0	5,509	493
Proceeds from sale of product line	11,832	0	0
Capital expenditures	(4,808)	(8,166)	(5,779)
Capital distribution from non-marketable investments	0	681	0
Purchase of technology rights	(736)	(2,362)	(3,250)
Net cash provided by (used in) investing activities	15,652	(258,933)	127,634
CASH FLOWS FROM FINANCING ACTIVITIES:
Issuance of common stock, net	825	276	(683)
Proceeds from term loan and revolver	48,000	80,500	0
Payments of term loan	(81,826)	(11,724)	0
Debt issuance costs	(1,080)	0	0
Proceeds from issuance of 4.00% convertible senior notes	0	101,062	0
Repurchase of 3.50% senior convertible notes	(3,855)	(91,614)	(3)
Excess tax benefits for share-based compensation	0	0	200
Net cash (used in) provided by financing activities	(37,936)	78,500	(486)
Effect of exchange rate changes on cash and cash equivalents	157	436	(32)
Net increase (decrease) in cash and cash equivalents	31,457	(176,266)	166,453
Cash and cash equivalents at beginning of period	25,671	201,937	35,484
Cash and cash equivalents at end of period	57,128	25,671	201,937
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION:
Cash paid for interest	12,456	6,968	3,341
Cash (paid) received for income taxes, net of refunds	$ (2,222)	$ 3,905	$ (633)