Stock-Based Compensation Plans - Restricted Share Unit Activity (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	$ 6.1		$ 6.1
Weighted average life over which unrecognized compensation is expected to be recognized			1 year 9 months 10 days
General and Administrative Expenses
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 4.2	$ 1.7	$ 5.0	$ 2.4
Restricted Stock Units
Incentive Share/Unit Awards
Unvested as of April 1, 2023			328,382
Granted			302,031
Vested			(326,665)
Unvested as of September 30, 2023	303,748		303,748
Weighted-Average Grant-Date Fair Value
Unvested as of April 1, 2023			$ 11.79
Granted			28.31
Vested			16.79
Unvested as of September 30, 2023	$ 22.83		$ 22.83