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Shareholders' Equity - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended		9 Months Ended
	Feb. 25, 2022	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Stockholders Equity Note [Line Items]
Shares withheld as payment for tax withholdings related to share based compensation, market value				$ 2,639	$ 2,471
ATM Program [Member]
Stockholders Equity Note [Line Items]
Maximum aggregate offering amount of stock	$ 300,000
Number of shares sold under ATM				45,000
Net proceeds from the sale of Common stock				$ 15,179
Direct costs				375
Available for sale under ATM Program		$ 284,745		$ 284,745
Common stock, issued		45,000		45,000
Class B Common Stock \| Restricted Stock
Stockholders Equity Note [Line Items]
Shares withheld as payment for tax withholdings related to share based compensation, shares			879		9,060
Shares withheld as payment for tax withholdings related to share based compensation, market value			$ 252		$ 2,431
Common and Class B Common Stock
Stockholders Equity Note [Line Items]
Cash dividends paid per share of Common and Class B common stock		$ 2.45	$ 2.2	$ 7.35	$ 6.35
Common and Class B Common Stock \| Restricted Stock
Stockholders Equity Note [Line Items]
Shares withheld as payment for tax withholdings related to share based compensation, shares		1,033		7,080
Shares withheld as payment for tax withholdings related to share based compensation, market value		$ 362		$ 2,026
Common Stock \| Employee Stock Option [Member]
Stockholders Equity Note [Line Items]
Net proceeds from the sale of Common stock		$ 5,983	$ 7,929	$ 18,677	$ 15,151
Shares withheld as payment for tax withholdings related to share based compensation, shares		295	1,053	17,687	1,053
Shares withheld as payment for tax withholdings related to share based compensation, market value		$ 106	$ 298	$ 5,489	$ 298
Common Stock \| Employee Stock Purchase Plan [Member]
Stockholders Equity Note [Line Items]
Net proceeds from shares purchased under ESPP		$ 563	$ 478	$ 1,696	$ 1,484