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Available for sale under AT-the-Market offering program.

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Direct costs.

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Maximum aggregate offering amount of stock.

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Shareholders' Equity - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Mar. 31, 2024	Jun. 30, 2025	Jun. 30, 2024	May 03, 2024	Mar. 29, 2024	Aug. 06, 2021
Stockholders Equity Note [Line Items]
Net proceeds from the sale of Common stock				$ 0	$ 281,784
Shares withheld as payment for tax withholdings related to share based compensation, market value				0	$ 1,209
2021 ATM Program [Member]
Stockholders Equity Note [Line Items]
Net proceeds from the sale of Common stock			$ 281,784
Maximum aggregate offering amount of stock								$ 300,000
Cumulative value of Common Stock sold under the 2021 ATM Program			298,455
Direct costs			$ 33
Number of shares sold and issued under ATM			712,000
2024 ATM Program [Member]
Stockholders Equity Note [Line Items]
Maximum aggregate offering amount of stock						$ 400,000
Available for sale under ATM Program	$ 400,000			$ 400,000
Dividend Reinvestment Plan [Member]
Stockholders Equity Note [Line Items]
Authorized shares of each of Common and Class B available for issuance under the Dividend Reinvestment Plan							300,000
Stock issued during period, shares, dividend reinvestment plan	16,553	4		30,495	4
Common and Class B Common Stock [Member] \| Restricted Stock [Member]
Stockholders Equity Note [Line Items]
Shares withheld as payment for tax withholdings related to share based compensation, shares		1,706			2,705
Shares withheld as payment for tax withholdings related to share based compensation, market value		$ 759			$ 1,150
Common Stock [Member]
Stockholders Equity Note [Line Items]
Cash dividends paid per share of common stock	$ 3	$ 2.7		$ 5.7	$ 5.15
Common Stock [Member] \| Stock Option [Member]
Stockholders Equity Note [Line Items]
Shares withheld as payment for tax withholdings related to share based compensation, shares	2,232	3,573		2,232	3,999
Shares withheld as payment for tax withholdings related to share based compensation, market value	$ 1,067	$ 1,685		$ 1,067	$ 1,860
Cash received from the exercise of stock options	2,462	5,912		12,860	15,952
Common Stock [Member] \| Employee Stock Purchase Plan [Member]
Stockholders Equity Note [Line Items]
Net proceeds from shares purchased under ESPP	$ 582	$ 568		$ 1,233	$ 1,151