CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2013
Statement of Financial Position [Abstract]
Trade accounts receivable, allowances (in dollars)	$ 18,218	$ 15,569	$ 25,068
Accumulated depreciation	129,002	103,090	99,473
Accumulated amortization	$ 37,316	$ 26,026	$ 24,140
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01	$ 0.01
Common stock, authorized shares	125,000,000us-gaap_CommonStockSharesAuthorized	125,000,000us-gaap_CommonStockSharesAuthorized	125,000,000us-gaap_CommonStockSharesAuthorized
Common stock, issued shares	33,292,000us-gaap_CommonStockSharesIssued	34,624,000us-gaap_CommonStockSharesIssued	34,618,000us-gaap_CommonStockSharesIssued
Common stock, outstanding shares	33,292,000us-gaap_CommonStockSharesOutstanding	34,624,000us-gaap_CommonStockSharesOutstanding	34,618,000us-gaap_CommonStockSharesOutstanding

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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