Capitalization (Detail) - USD ($) $ / shares in Units, shares in Thousands	2 Months Ended	12 Months Ended
Mar. 31, 2021	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2019
Class of Stock [Line Items]
Common stock, shares outstanding (in shares)	46,482	46,482	46,011
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01	$ 0.01
Amount of common stock repurchased	$ 62,127,000	$ 95,259,000	$ 77,198,000	$ 132,697,000
Number of shares repurchased (in shares)		1,643
Share repurchase program, authorized amount available	$ 200,000,000	$ 200,000,000
Percentage of free cash flow used for additional stock repurchases	75.00%	75.00%
Capital shares reserved for future issuance (in shares)	5,075	5,075

Stock Repurchase Program, Percentage Of Free Cash Flow Used For Additional Repurchases

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Aggregate number of common shares reserved for future issuance.

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- Definition

Face amount or stated value per share of common stock.

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

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Amount of stock repurchase plan authorized.

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- Definition

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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