CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2018	Mar. 31, 2018
Statement of Financial Position [Abstract]
Trade accounts receivable, allowances	$ 14,019	$ 33,462
Inventory reserves	8,136	9,020
Accumulated depreciation	219,969	210,763
Accumulated amortization	$ 68,755	$ 66,065
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, authorized shares (in shares)	125,000,000	125,000,000
Common stock, issued shares (in shares)	29,371,000	30,447,000
Common stock, outstanding shares (in shares)	29,371,000	30,447,000

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

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Amount of inventory reserves for last-in first-out (LIFO) and other inventory valuation methods.

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