Segment Information - Summary Of Revenue From External Customers By Geographic Areas (Details) - USD ($) $ in Millions	12 Months Ended
Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2022
Revenue	$ 2,986.4	$ 3,083.8	$ 2,716.3
Canada
Revenue	70.4	64.0	56.7
United States
Revenue	2,262.3	2,348.8	2,084.0
Other foreign
Revenue	$ 653.7	$ 671.0	$ 575.6

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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+ Details