Schedule Of Computation of Earnings Per Share - Summary of Calculation of Basic Earnings Per Common Share and Diluted Earnings Per Common Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2024	Mar. 31, 2024	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2024	Jun. 30, 2023
Numerator:
Net Income (Loss)	$ 102,519	$ 90,695	$ 91,319	$ 76,097	$ 193,214	$ 167,416
Denominator:
Denominator for basic earnings per share-weighted average common shares	26,691		26,634		26,682	26,617
Dilutive effect of share-based awards	111		102		116	105
Denominator for diluted earnings per share-adjusted weighted average common shares	26,802		26,736		26,798	26,722
Basic Earnings Per Share	$ 3.84		$ 3.43		$ 7.24	$ 6.29
Diluted Earnings Per Share	$ 3.83		$ 3.42		$ 7.21	$ 6.27