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Revenue Recognition - Additional Information (Detail) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020 | Mar. 31, 2021
Contract With Customer Assets And Liabilities [Line Items] |  |  |  |  |
Percentage of revenue from contracts recognized over time | 80.00% | 60.00% | 75.00% | 50.00% |
Percentage of revenue from contracts recognized upon shipment | 20.00% | 40.00% | 25.00% | 50.00% |
Revenue recognized included in contract liability | $ 13,293 |  | $ 13,293 |  |
Unbilled revenue (contract assets) |  |  | 9,041 |  |
Contract with customer liability increase in contract asset due to contract progress. |  |  | 19,828 |  |
Contract with customer liability offset by invoicing to customers. |  |  | 17,855 |  |
Customer deposits, current |  |  | 7,882 |  |
Contract with customer liability offset by new customer deposits. |  |  | 15,127 |  |
Receivables billed but not paid under retainage provisions in its customer contracts | 3,364 |  | 3,364 |  | $ 3,747
Amortization expense | 24 | $ 89 | 34 | $ 251 |
Revenue remaining unsatisfied performance obligations amount | 233,247 |  | 233,247 |  |
Barber-Nichols, LLC. (BN) [Member] |  |  |  |  |
Contract With Customer Assets And Liabilities [Line Items] |  |  |  |  |
Acquisition of contract assets |  |  | 7,068 |  |
Acquisition of contract liabilities |  |  | 6,048 |  |
Customer Deposit [Member] |  |  |  |  |
Contract With Customer Assets And Liabilities [Line Items] |  |  |  |  |
Contract liabilities | 2,902 |  | 2,902 |  | 1,603
Prepaid Expenses and Other Current Assets [Member] |  |  |  |  |
Contract With Customer Assets And Liabilities [Line Items] |  |  |  |  |
Capitalized costs, net of amortization | $ 79 |  | $ 79 |  | $ 39

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