Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2020	Mar. 31, 2020
Statement Of Financial Position [Abstract]
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	120,000,000	120,000,000
Common stock, shares issued	54,439,754	54,254,557
Common stock, shares outstanding	17,887,043	17,968,966
Treasury stock, shares	36,552,711	36,285,591

Face amount or stated value per share of common stock.

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-Section S99
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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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-Topic 505
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Number of previously issued common shares repurchased by the issuing entity and held in treasury.

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