Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Allowances for accounts receivable	$ 47,000	$ 28,600
Preferred stock, par value (USD per share)		$ 1.00
Preferred stock, shares authorized	5,000,000us-gaap_PreferredStockSharesAuthorized	5,000,000us-gaap_PreferredStockSharesAuthorized
Preferred stock, shares issued		0us-gaap_PreferredStockSharesIssued
Preferred stock, shares outstanding		0us-gaap_PreferredStockSharesOutstanding
Common stock, par value (USD per share)		$ 0.001
Common stock, shares authorized		125,000,000us-gaap_CommonStockSharesAuthorized
Common stock, share issued	67,667,468us-gaap_CommonStockSharesIssued	66,590,875us-gaap_CommonStockSharesIssued
Common stock, shares outstanding	65,474,486us-gaap_CommonStockSharesOutstanding	64,397,893us-gaap_CommonStockSharesOutstanding
Treasury stock	2,192,982us-gaap_TreasuryStockShares	2,192,982us-gaap_TreasuryStockShares

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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