Equity Method Investments and Related-Party Transactions - Schedule of Related Party Transactions (Detail) - Euro Infrastructure Co [Member] - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2019
Related Party Transaction [Line Items]
Revenue	$ 10,619	$ 9,993	$ 8,365
Expense	16,341	18,854	14,302
Cash received	10,800	12,848	11,276
Cash paid	27,079	13,463	$ 15,191
Collections in excess of revenues and deferred revenues	$ 6,013	5,832
Accounts payable		$ 5,446

Amount for accounts payable to related parties.

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