Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Cash flows from operating activities:
Net income (loss)	$ (63,997)	$ 19,991
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Non-cash impairment charge	104,245
Non-cash share-based compensation expense	5,992	4,904
Non-cash interest expense	2,409	2,245
Non-cash charge for contingent consideration	422	1,112
Non-cash charge for option amortization	1,084	1,071
Deferred tax benefit	(46,128)	(4,381)
Depreciation and amortization expense	9,739	9,561
Other, net	3,182	(2,477)
Changes in assets and liabilities:
Accounts receivable	15,719	15,353
Inventory	(10,481)	4,289
Prepaid expenses and other current assets	1,333	608
Prepaid income taxes and income taxes payable	3,768	(6,069)
Other assets	(531)	670
Accounts payable	(4,181)	4,840
Accrued expenses and other current liabilities	(7,878)	1,697
Other non-current liabilities	(834)	(103)
Net cash provided by operating activities	13,863	53,311
Cash flows from investing activities:
Purchase of property, equipment and building improvements	(857)	(267)
Purchase of short-term investments	(20,150)	(36,192)
Maturities and sales of short-term investments	29,650	54,353
Net cash provided by investing activities	8,643	17,894
Cash flows from financing activities:
Payment for treasury shares acquired		(49,996)
Net proceeds from issuance of common stock	1,605	5,558
Excess tax benefits from share-based payment arrangements	417	4,827
Net cash provided by (used in) financing activities	2,022	(39,611)
Effect of exchange rate changes on cash	(849)	699
Net increase in cash and cash equivalents	23,679	32,293
Cash and cash equivalents at beginning of period	175,518	331,352
Cash and cash equivalents at end of period	$ 199,197	$ 363,645