CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Current assets
Accounts receivable allowance	$ 2,618	$ 2,181
Employee loans current allowance	0	0
Noncurrent assets
Employee loans long-term allowance	$ 0	$ 0
Stockholders' equity
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	160,000,000us-gaap_CommonStockSharesAuthorized	160,000,000us-gaap_CommonStockSharesAuthorized
Common stock, shares issued (in shares )	49,111,297us-gaap_CommonStockSharesIssued	48,748,298us-gaap_CommonStockSharesIssued
Common stock, shares outstanding (in shares)	48,692,313us-gaap_CommonStockSharesOutstanding	48,303,811us-gaap_CommonStockSharesOutstanding

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 4

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-Name Accounting Standards Codification

-Topic 210

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-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.4)

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A valuation allowance for doubtful other receivables due to an entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible and not separately disclosed.

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No definition available.

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A valuation allowance relating to a written agreement to receive money (at a specified future date(s) more than one year from the reporting date, consisting of principal as well as any accrued interest) for the portion that is expected to be uncollectible.

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- Definition

Face amount or stated value per share of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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