Consolidated Statements of Comprehensive Loss (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Statement of Comprehensive Income [Abstract]
Net loss	$ (53,916)us-gaap_NetIncomeLoss	$ (162,013)us-gaap_NetIncomeLoss	$ (171,855)us-gaap_NetIncomeLoss
Other comprehensive income (loss):
Net unrealized (loss) gain on available-for-sale investments	(95)	(268)	1,206
Income tax provision (benefit) on unrealized gain on available-for-sale investments		470	(470)
Net foreign currency translation (loss) gain	(291)	(1,026)	10
Other comprehensive income (loss), net of tax	(386)	(824)	746
Comprehensive loss	$ (54,302)us-gaap_ComprehensiveIncomeNetOfTax	$ (162,837)us-gaap_ComprehensiveIncomeNetOfTax	$ (171,109)us-gaap_ComprehensiveIncomeNetOfTax

This item represents the pretax change in net unrealized holding gain (loss) on available-for-sale securities that has been included in accumulated other comprehensive income, a separate component of shareholders' equity, during the period.

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This item represents the tax effects occurring during the period which are related to the net unrealized gain (loss) resulting from changes in the fair [carrying] value during the period of available-for-sale securities. Such tax affects would have been charged or credited directly to other comprehensive income or to related components of shareholders' equity.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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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 gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature, attributable to noncontrolling interests.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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