Weighted Average Shares and Net Income Per Share - Calculations of Basic and Diluted Weighted Average Common Shares (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2023	Dec. 31, 2022
Earnings Per Share [Abstract]
Net Income	$ 17,095,000	$ 16,849,000	$ 56,798,000	$ 48,196,000
Basic:
Weighted average common shares outstanding	17,106,000	17,245,000	17,124,000	17,379,000
Net Income per share	$ 1	$ 0.98	$ 3.32	$ 2.77
Diluted:
Weighted average common shares outstanding	17,106,000	17,245,000	17,124,000	17,379,000
Treasury stock impact of stock options	220,000	242,000	228,000	268,000
Total common and common equivalent shares	17,326,000	17,487,000	17,352,000	17,647,000
Net Income per share	$ 0.99	$ 0.96	$ 3.27	$ 2.73