Earnings Per Share - Basic and Diluted Weighted Average Shares Outstanding Used to Compute Earnings Per Share (Detail) - $ / shares shares in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Earnings Per Share [Abstract]
Basic weighted average shares outstanding	35,203	37,210	35,252	37,299
Dilutive effect of stock options and full value awards	39	88	62	78
Diluted weighted average shares outstanding	35,242	37,298	35,314	37,377
Basic earnings per share	$ 1.93	$ 1.91	$ 4.14	$ 2.31
Diluted earnings per share	$ 1.93	$ 1.91	$ 4.13	$ 2.31