Equity Method Investments and Related-Party Transactions - Additional Information (Detail) - USD ($)	1 Months Ended	3 Months Ended		9 Months Ended
	Mar. 31, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2017	Dec. 31, 2016
Schedule of Equity Method Investments [Line Items]
Foreign currency translation adjustments, net of tax		$ 3,619,000	$ (1,331,000)	$ 13,465,000	$ (2,270,000)
Income (loss) from equity method investments		1,365,000		1,593,000
Euro Infrastructure Co [Member]
Schedule of Equity Method Investments [Line Items]
Payments, net of transaction costs, to acquire the issued shares in investment	$ 139,500,000
Equity method investment ownership percentage	49.00%
Foreign currency translation adjustments, net of tax		3,200,000		$ 10,900,000
Estimated useful life, years				11 years
Estimated weighted average life (In years)				10 years
Tangible assets, useful life				11 years
Tangible assets, weighted average useful life				11 years
Income (loss) from equity method investments		1,400,000	$ 0	$ 1,600,000	$ 0
Retained earnings of undistributed cumulative earnings in equity interests, net of tax		$ 1,600,000		$ 1,600,000