Income Taxes (Details 4) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Income before provision for Income Taxes
Federal tax benefit, at statutory rate	$ (30,142)	$ (11,694)	$ (8,690)
State benefit, net of federal benefit	(757)	(733)	(509)
Change in valuation allowance-current year	27,486	14,612	7,888
Change in valuation allowance-prior year deferreds	0	0	14,840
Tax expense/ (benefit) from business combination	0	909	(4,838)
Research and development credits	(856)	(1,731)	(2,044)
Share-based compensation	1,616	526	917
Merger fees	0	0	674
Uncertain tax positions	(46)	(11,809)	322
Goodwill impairment	3,700	596	0
Other	(390)	(179)	(667)
Provision (benefit) for income taxes	$ 611	$ (9,503)	$ 7,893

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Income tax reconciliation business combination.

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Income tax reconciliation change in valuation allowance prior year deferred.

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Income tax reconciliation nondeductible expense merger fees.

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The sum of the current income tax expense or benefit and the deferred income tax expense or benefit pertaining to continuing operations.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to nondeductible expenses under enacted tax laws, or differences in the methodologies used to determine expense amounts for financial statements prepared in accordance with generally accepted accounting principles, not otherwise listed in the existing taxonomy.

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to differences in the deductibility of incentive stock options and other equity-based compensation costs in accordance with generally accepted accounting principles and enacted tax laws.

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The portion of the difference, between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations, that is attributable to state and local income tax expense or benefit.

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to research tax credits generated or utilized under enacted tax laws during the period.

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