Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Operating activities:
Net income (loss)	$ (25,463)	$ (159,606)	$ 12,346
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities, net of the effect of acquisitions:
Depreciation and amortization	4,430	10,177	11,778
Goodwill and long-lived asset impairment		112,904
Change in fair value of contingent liability	(1,210)
Loss on disposal of fixed assets	163	181	29
Lease incentives		2,223
Provision for adjustments to accounts receivable and doubtful accounts	1,045	1,244	851
Provision for excess and obsolete inventory	73	158	203
Tax benefits from stock-based compensation			(1,543)
Non cash compensation related to stock options and restricted stock	3,949	6,530	9,496
Deferred income taxes		414	849
Change in operating accounts, net of effect from acquisitions:
Accounts receivable	(1,473)	20,043	(6,516)
Income tax receivable	7,612	(5,421)	(1,892)
Inventories	60	(97)	(167)
Prepaid expenses and other assets	268	58	259
Accounts payable and accrued liabilities	(2,259)	(2,355)	(949)
Net cash provided by (used in) operating activities	(12,805)	(13,547)	24,744
Investing activities:
Acquisitions, net of cash received			(532)
Capital expenditures	(322)	(13,431)	(6,312)
Sale (purchase) of short-term investments	25,196	16,172	(23,418)
Net cash provided by (used in) investing activities	24,874	2,741	(30,262)
Financing activities:
Tax benefits from stock-based compensation			1,543
Cash received from stock sale for employee stock purchase plan	66	413
Cash received from exercise of stock options	16	12	7,254
Repurchase of common stock	(753)
Net cash provided by (used in) financing activities	(671)	425	8,797
Net increase (decrease) in cash and cash equivalents	11,398	(10,381)	3,279
Cash and cash equivalents, beginning of period	7,475	17,856	14,577
Cash and cash equivalents, end of period	18,873	7,475	17,856
Supplemental disclosures of cash flow information:
Cash paid for income taxes	$ 257	$ 700	$ 5,776