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Intangible Assets - Schedule of Intangible assets (Detail) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Mar. 31, 2024 | Mar. 31, 2023
Finite Lived Intangible Assets [Line Items] |  |
Intangibles subject to amortization, Gross Carrying Amount | $ 33,000 | $ 25,800
Intangibles subject to amortization, Accumulated Amortization | 7,155 | 4,998
Total intangible amortization | 25,845 | 20,802
Intangibles not subject to amortization, Gross Carrying Amount | 6,700 | 6,700
Intangibles not subject to amortization, Net Carrying Amount | 6,700 | $ 6,700
Customer Relationships [Member] |  |
Finite Lived Intangible Assets [Line Items] |  |
Intangibles subject to amortization, Weighted Average Amortization Period |  | 20 years
Intangibles subject to amortization, Gross Carrying Amount | 16,200 | $ 11,800
Intangibles subject to amortization, Accumulated Amortization | 1,901 | 1,082
Total intangible amortization | $ 14,299 | $ 10,718
Customer Relationships [Member] | Maximum [Member] |  |
Finite Lived Intangible Assets [Line Items] |  |
Intangibles subject to amortization, Weighted Average Amortization Period | 20 years |
Customer Relationships [Member] | Minimum [Member] |  |
Finite Lived Intangible Assets [Line Items] |  |
Intangibles subject to amortization, Weighted Average Amortization Period | 8 years |
Technology and Technical Know How [Member] |  |
Finite Lived Intangible Assets [Line Items] |  |
Intangibles subject to amortization, Weighted Average Amortization Period |  | 20 years
Intangibles subject to amortization, Gross Carrying Amount | $ 12,600 | $ 10,100
Intangibles subject to amortization, Accumulated Amortization | 1,535 | 926
Total intangible amortization | $ 11,065 | $ 9,174
Technology and Technical Know How [Member] | Maximum [Member] |  |
Finite Lived Intangible Assets [Line Items] |  |
Intangibles subject to amortization, Weighted Average Amortization Period | 20 years |
Technology and Technical Know How [Member] | Minimum [Member] |  |
Finite Lived Intangible Assets [Line Items] |  |
Intangibles subject to amortization, Weighted Average Amortization Period | 10 years |
Backlog [Member] |  |
Finite Lived Intangible Assets [Line Items] |  |
Intangibles subject to amortization, Weighted Average Amortization Period | 4 years | 4 years
Intangibles subject to amortization, Gross Carrying Amount | $ 3,900 | $ 3,900
Intangibles subject to amortization, Accumulated Amortization | 3,677 | 2,990
Total intangible amortization | $ 223 | $ 910
Tradename [Member] |  |
Finite Lived Intangible Assets [Line Items] |  |
Intangibles subject to amortization, Weighted Average Amortization Period | 3 years |
Intangibles subject to amortization, Gross Carrying Amount | $ 300 |
Intangibles subject to amortization, Accumulated Amortization | 42 |
Total intangible amortization | $ 258 |
Tradename [Member] |  |
Finite Lived Intangible Assets [Line Items] |  |
Intangibles not subject to amortization, Weighted Average Amortization Period | Indefinite | Indefinite
Intangibles not subject to amortization, Gross Carrying Amount | $ 6,700 | $ 6,700
Intangibles not subject to amortization, Net Carrying Amount | $ 6,700 | $ 6,700

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- Definition Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 350 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (a)(3) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482665/350-30-50-1 + Details
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