Related Party Transactions (Related Party Revenue) (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2020
Related party transactions:
Management fees revenue	$ 35,194	$ 31,603	$ 30,406
Revenue from related parties	35,194	31,603	30,406
Blackwater [Member]
Related party transactions:
Management fees revenue	28,546	25,512	24,014
Mercury [Member]
Related party transactions:
Management fees revenue	$ 6,648	$ 6,091	$ 6,392

Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

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+ Details