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, 2023	Mar. 31, 2023	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2023	Jun. 30, 2022
Numerator:
Net income	$ 91,319	$ 76,097	$ 109,245	$ 79,424	$ 167,416	$ 188,669
Denominator:
Denominator for basic earnings per share-weighted average common shares	26,634		26,507		26,617	26,489
Dilutive effect of share-based awards	102		158		105	173
Denominator for diluted earnings per share-adjusted weighted average common shares	26,736		26,665		26,722	26,662
Basic Earnings Per Share	$ 3.43		$ 4.12		$ 6.29	$ 7.12
Diluted Earnings Per Share	$ 3.42		$ 4.10		$ 6.27	$ 7.08