Equity Method Investments and Related Party Transactions - Schedule of Related Party Transactions (Detail) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Euro Infrastructure Co [Member]
Related Party Transaction [Line Items]
Revenue	$ 8,365	$ 9,277
Expense	14,302	7,134
Cash received	11,276	7,460
Cash paid	15,191	7,040
Accounts receivable		3,307
Collections in excess of revenues and deferred revenues	4,703	3,246
Ducommun Inc. [Member]
Related Party Transaction [Line Items]
Cash paid	$ 20,059
Accounts payable		$ 2,073

Amount for accounts payable to related parties.

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