Equity Method Investments and Related-Party Transactions - The Difference Between Carrying Value of Investment in Euro Infrastructure Co. and Proportionate Share of Net Assets of Euro Infrastructure Co. (Detail) $ in Thousands	Mar. 31, 2021 USD ($)
Schedule of Equity Method Investments [Line Items]
Investment in unconsolidated affiliate	$ 176,938
EBI [Member]
Schedule of Equity Method Investments [Line Items]
Investment in unconsolidated affiliate	176,938
Less: proportionate share of net assets of Euro Infrastructure Co.	159,394
Excess carrying value of investment over proportionate share of net assets	17,544
EBI [Member] | Goodwill [Member]
Schedule of Equity Method Investments [Line Items]
Excess carrying value of investment over proportionate share of net assets	23,978
EBI [Member] | Identifiable Intangible Assets [Member]
Schedule of Equity Method Investments [Line Items]
Excess carrying value of investment over proportionate share of net assets	8,332
EBI [Member] | Tangible Assets [Member]
Schedule of Equity Method Investments [Line Items]
Excess carrying value of investment over proportionate share of net assets	(15,781)
EBI [Member] | Deferred Income Taxes [Member]
Schedule of Equity Method Investments [Line Items]
Excess carrying value of investment over proportionate share of net assets	$ 1,015