Equity Method Investments and Related-Party Transactions - Schedule of Related Party Transactions (Detail) - Euro Infrastructure Co [Member] - USD ($) $ in Thousands	3 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Mar. 31, 2019
Related Party Transaction [Line Items]
Revenue	$ 3,753	$ 1,851
Expense	3,197	2,159
Cash received		2,430
Cash paid	2,995	$ 1,947
Accounts receivable	1,936
Collections in excess of revenues and deferred revenues	$ 1,438		$ 4,703

For an unclassified balance sheet, amount of receivables arising from transactions with related parties.

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