CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2019	Mar. 31, 2019
Statement of Financial Position [Abstract]
Trade accounts receivable, allowances	$ 10,045	$ 18,824
Inventory reserves	8,808	9,723
Accumulated depreciation	243,624	235,939
Accumulated amortization	$ 72,762	$ 71,186
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)	28,965,000	29,141,000
Common stock, outstanding shares (in shares)	28,965,000	29,141,000

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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Amount of allowance for credit loss on accounts receivable, classified as current.

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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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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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