Earnings Per Share - Reconciliation of Numerator and Denominator of Basic Earnings Per Share with that of Diluted Earnings Per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Earnings Per Share [Abstract]
Distributed earnings allocated to common stock	$ 52,402	$ 49,904	$ 105,913	$ 100,278
Undistributed earnings allocated to common stock	68,046	46,386	98,660	82,627
Net earnings allocated to common shareholders	$ 120,448	$ 96,290	$ 204,573	$ 182,905
Average common shares outstanding	142,206,539	135,137,901	142,175,506	134,881,314
Equivalents from stock options	237,958	176,884	290,037	221,974
Average diluted shares outstanding	142,444,497	135,314,785	142,465,543	135,103,288
Earnings per basic common share	$ 0.85	$ 0.71	$ 1.44	$ 1.36
Earnings per diluted common share	$ 0.85	$ 0.71	$ 1.44	$ 1.35

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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- Definition

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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- Definition

Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders.

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