Equity Method Investments and Related-Party Transactions - Schedule of Related Party Transactions (Detail) - Euro Infrastructure Co [Member] - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Mar. 31, 2020
Related Party Transaction [Line Items]
Revenue		$ 4,599	$ 1,424	$ 8,352
Expense	$ 4,004	5,708	8,168	8,905
Cash received	4,820	1,490	8,222	2,352
Cash paid	4,886	$ 4,462	13,080	$ 7,456
Collections in excess of revenues and deferred revenues	$ 12,630		$ 12,630		$ 5,832
Accounts payable					$ 5,446

Amount for accounts payable to related parties.

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