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Stock-Based Compensation Plans - Narrative (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Oct. 31, 2021	Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2024	Apr. 30, 2014
Stock-Based Compensation Plans
Number of shares authorized					2,850,000
Additional shares authorized	2,015,000
Options granted		38,578	29,741	31,400
Stock-based compensation expense		$ 11.0	$ 10.4	$ 8.3
Unrecognized compensation cost		$ 5.3
Recognition period		1 year 1 month 13 days
Restricted stock
Stock-Based Compensation Plans
Fair value of restricted share vested during the period		$ 9.8	$ 13.0	$ 10.5
Restricted stock \| Vesting ratably on the grant date and on the first, second and third anniversary of that date
Stock-Based Compensation Plans
Shares granted				264,750
Restricted stock \| Vesting ratably on the grant date and on the first, and second anniversary of that date
Stock-Based Compensation Plans
Shares granted		232,278	231,150
Restricted stock \| Vesting on the grant date
Stock-Based Compensation Plans
Shares granted			16,000
Restricted Stock Units \| Vesting ratably on the grant date and on the first, and second anniversary of that date
Stock-Based Compensation Plans
Shares granted		63,266	48,960	45,500