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Share Repurchase Program - Additional Information (Detail) - USD ($)	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 19, 2022	May 06, 2021
Equity, Class of Treasury Stock [Line Items]
Common stock repurchase program, number of shares repurchased (in shares)	270,080	497,243
Repurchase program, approximate dollar value of shares purchased	$ 25,008,025	$ 49,999,979
Repurchase program, average price paid per share (in usd per share)	$ 92.59	$ 100.55
May 6, 2021 Stock Repurchase Program
Equity, Class of Treasury Stock [Line Items]
Common stock repurchase program, authorized amount				$ 125,000,000
Common stock repurchase program, authorized remaining amount			$ 50,000,000
September 14, 2022 Stock Repurchase Program
Equity, Class of Treasury Stock [Line Items]
Common stock repurchase program, authorized amount			$ 300,000,000
Common stock repurchase program, authorized remaining amount	$ 300,000,000

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Amount of stock repurchase plan authorized.

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Number of shares that have been repurchased and retired during the period.

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Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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