Net Loss per Share (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Basic and diluted
Net loss	$ (18,542)	$ (115,344)	$ (83,862)
Weighted-average common shares outstanding	93,410	84,493	72,103
Less: unvested RSAs (in shares)	(2,501)	(2,442)	(33)
Weighted-average shares used in computing basic net loss per share	90,909	82,051	72,070
Basic and diluted net loss per share (in dollars per share)	$ (0.20)	$ (1.41)	$ (1.16)
Securities that could potentially dilute basic EPS in the future
Anti-dilutive securities (in shares)	12,035	12,132	13,304
Equity Incentive Plans and ESPP
Securities that could potentially dilute basic EPS in the future
Anti-dilutive securities (in shares)	5,367	5,464	6,636
Convertible subordinated notes
Securities that could potentially dilute basic EPS in the future
Anti-dilutive securities (in shares)	6,668	6,668	6,668

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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+ Details

- Definition

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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+ Details

- Definition

Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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-URI http://asc.fasb.org/extlink&oid=6528421

+ Details