Net Loss per Share (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Numerator:
Loss from continuing operations, net of tax	$ (20,151)	$ (1,541)	$ (36,333)	$ (12,287)
Loss from discontinued operations	(43,413)	(34,888)	(94,934)	(61,502)
Net loss	$ (63,564)	$ (36,429)	$ (131,267)	$ (73,789)
Denominator:
Weighted-average number of shares outstanding	113,163	100,316	112,608	99,677
Less: unvested RSAs (in shares)	(2,189)	(2,713)	(2,189)	(2,713)
Weighted-average number of shares used to compute basic and diluted net loss per share	110,974	97,603	110,419	96,964
Basic and diluted net loss per share (in dollars per share)
Continuing operations, net of tax (in dollars per share)	$ (0.18)	$ (0.02)	$ (0.33)	$ (0.13)
Discontinued operations (in dollars per share)	$ (0.39)	$ (0.35)	$ (0.86)	$ (0.63)
Basic and diluted net loss per share (in dollars per share)	$ (0.57)	$ (0.37)	$ (1.19)	$ (0.76)
Securities that could potentially dilute basic EPS in the future
Anti-dilutive securities (in shares)	24,005	20,863	23,811	20,162
Equity incentive plans and ESPP
Securities that could potentially dilute basic EPS in the future
Anti-dilutive securities (in shares)	6,136	3,848	5,942	4,519
Convertible subordinated notes
Securities that could potentially dilute basic EPS in the future
Anti-dilutive securities (in shares)	17,869	17,015	17,869	15,643

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- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Amount of income (loss) from continuing operations attributable to the parent. Also defined as revenue less expenses and taxes from ongoing operations before extraordinary items but after deduction of those portions of income or loss from continuing operations that are allocable to noncontrolling interests.

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The amount of net income (loss) from continuing operations per each basic and diluted share of common stock or unit when the per share amount is the same for both basic and diluted shares.

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- Definition

Amount of income (loss) from a disposal group, net of income tax before extraordinary items allocable to noncontrolling interests. Includes, net of tax, income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

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Per basic and diluted share amount, after tax, of income (loss) from the day-to-day business activities of the discontinued operation and gain (loss) from the disposal of the discontinued operation, when the per share amount is the same.

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Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

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Average number of shares or units issued and outstanding that are used in calculating basic and diluted earnings per share (EPS).

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This element represents the weighted average total number of shares issued throughout the period including the first (beginning balance outstanding) and last (ending balance outstanding) day of the period before considering any reductions (for instance, shares held in treasury) to arrive at the weighted average number of shares outstanding. Weighted average relates to the portion of time within a reporting period that common shares have been issued and outstanding to the total time in that period. Such concept is used in determining the weighted average number of shares outstanding for purposes of calculating earnings per share (basic).

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Number of shares of restricted stock determined by relating the portion of time within a reporting period that restricted shares have been outstanding to the total time in that period. Restricted shares are subject to sales, contractual, regulatory or other restrictions that prevent or inhibit the holder from freely disposing of them before the restriction ends.

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