Schedule of Stock Repurchase Activity (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Stockholders' Equity Note [Abstract]
Shares repurchased	67,649	465,687
Average price per share	$ 167.19	$ 182.27
Value of shares repurchased (in thousands)	$ 11,310	$ 84,879

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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