Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Current assets:
Allowance for doubtful accounts	$ 10,153	$ 10,826
Equity:
Preferred stock, par value (in dollars per share)	$ 0.00001	$ 0.00001
Preferred stock, shares authorized (in shares)	500us-gaap_PreferredStockSharesAuthorized	500us-gaap_PreferredStockSharesAuthorized
Preferred stock, shares issued (in shares)	0us-gaap_PreferredStockSharesIssued	0us-gaap_PreferredStockSharesIssued
Preferred stock, shares outstanding (in shares)	0us-gaap_PreferredStockSharesOutstanding	0us-gaap_PreferredStockSharesOutstanding
Common stock, par value (in dollars per share)	$ 0.00001	$ 0.00001
Common stock, shares authorized (in shares)	180,000us-gaap_CommonStockSharesAuthorized	180,000us-gaap_CommonStockSharesAuthorized
Common stock, shares issued (in shares)	90,914us-gaap_CommonStockSharesIssued	89,343us-gaap_CommonStockSharesIssued
Common stock, shares outstanding (in shares)	90,914us-gaap_CommonStockSharesOutstanding	89,343us-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.

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