Equity Method Investments and Related-Party Transactions - Schedule of Related Party Transactions (Detail) - Euro Infrastructure Co [Member] $ in Thousands	3 Months Ended	9 Months Ended
Dec. 31, 2017 USD ($)	Dec. 31, 2017 USD ($)
Related Party Transaction [Line Items]
Revenue	$ 1,945	$ 7,574
Expense	1,725	5,313
Cash received	2,191	6,540
Cash paid	1,407	5,416
Accounts receivable	1,857	1,857
Collections in excess of revenues and deferred revenues	$ 2,580	$ 2,580

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

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