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, 2020	Mar. 31, 2019	Mar. 31, 2018
Related Party Transaction [Line Items]
Revenue	$ 9,993	$ 8,365	$ 9,277
Expense	18,854	14,302	7,134
Cash received	12,848	11,276	7,460
Cash paid	13,463	15,191	$ 7,040
Collections in excess of revenues and deferred revenues	5,832	$ 4,703
Accounts payable	$ 5,446

Amount for accounts payable to related parties.

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