Weighted Average Shares and Net Income Per Share - Calculations of Basic and Diluted Weighted Average Common Shares (Detail) - USD ($)	3 Months Ended
	Jun. 30, 2024	Jun. 30, 2023
Earnings Per Share [Abstract]
Net Income	$ 21,577,000	$ 19,805,000
Basic:
Weighted average common shares outstanding	17,122,000	17,144,000
Net Income per share	$ 1.26	$ 1.16
Diluted:
Weighted average common shares outstanding	17,313,000	17,385,000
Treasury stock impact of stock options	191,000	241,000
Total common and common equivalent shares	17,313,000	17,385,000
Net Income per share	$ 1.25	$ 1.14