Consolidated Statements of Stockholders' Equity (USD $) In Thousands, except Share data	Total	Common Stock and Additional Paid-In Capital [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Accumulated Deficit [Member]	Treasury Stock [Member]
Beginning balance at Dec. 31, 2011	$ 37,891us-gaap_StockholdersEquity	$ 182,508	$ 118	$ (119,887)	$ (24,848)
Beginning balance, shares at Dec. 31, 2011		31,786,030			3,928,206
Net income (loss)	(7,197)us-gaap_NetIncomeLoss			(7,197)
Unrealized gain (loss) on available-for-sale securities, net of taxes	(9)		(9)
Repurchase of stock	(5,721)				(5,721)
Repurchase of stock, shares	1,054,538us-gaap_TreasuryStockSharesAcquired				1,054,538
Issuance of stock for ESPP purchase	122	122
Issuance of stock for ESPP purchase, shares		25,628
Exercise of stock options	1,046	1,046
Exercise of stock options, shares		231,403
Release of restricted stock units and awards	1,299	1,299
Release of restricted stock units and awards, shares		235,269
Stock based compensation	1,847	1,847
Ending balance at Dec. 31, 2012	29,278us-gaap_StockholdersEquity	186,822	109	(127,084)	(30,569)
Ending balance, shares at Dec. 31, 2012		32,278,330			4,982,744
Net income (loss)	40,155us-gaap_NetIncomeLoss			40,155
Unrealized gain (loss) on available-for-sale securities, net of taxes	3		3
Repurchase of stock, shares	0us-gaap_TreasuryStockSharesAcquired
Issuance of stock for ESPP purchase	198	198
Issuance of stock for ESPP purchase, shares		36,921
Exercise of stock options	6,393	6,393
Exercise of stock options, shares		956,633
Release of restricted stock units and awards	3,482	3,482
Release of restricted stock units and awards, shares		347,882
Stock based compensation	1,162	1,162
Ending balance at Dec. 31, 2013	80,671us-gaap_StockholdersEquity	198,057	112	(86,929)	(30,569)
Ending balance, shares at Dec. 31, 2013		33,619,766			4,982,744
Net income (loss)	4,123us-gaap_NetIncomeLoss			4,123
Unrealized gain (loss) on available-for-sale securities, net of taxes	(10)		(10)
Repurchase of stock	(15,000)				(15,000)
Repurchase of stock, shares	1,527,647us-gaap_TreasuryStockSharesAcquired				1,527,647
Issuance of stock for ESPP purchase	381	381
Issuance of stock for ESPP purchase, shares		38,298
Exercise of stock options	1,304	1,304
Exercise of stock options, shares		205,744
Release of restricted stock units and awards	3,976	3,976
Release of restricted stock units and awards, shares		361,970
Tax benefit/(deficiency) from the stock incentive plans	(161)	(161)
Stock based compensation	1,319	1,319
Ending balance at Dec. 31, 2014	$ 76,603us-gaap_StockholdersEquity	$ 204,876	$ 102	$ (82,806)	$ (45,569)
Ending balance, shares at Dec. 31, 2014		34,225,778			6,510,391

Number of shares issued during the period related to restricted stock units and awards, net of any shares forfeited.

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Value of stock related to restricted stock units and awards issued during the period, net of the stock value of such awards forfeited.

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This element represents the amount of recognized equity-based compensation during the period, that is, the amount recognized as expense in the income statement (or as asset if compensation is capitalized). Alternate captions include the words "stock-based compensation".

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Amount of increase (decrease) in additional paid in capital (APIC) resulting from a tax benefit (deficiency) associated with an share-based compensation plan other than an employee stock ownership plan (ESOP).

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount after tax and reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities, attributable to parent entity. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Number of shares of stock issued as of the balance sheet date, including shares that had been issued and were previously outstanding but which are now held in the treasury.

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Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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