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Intangible Assets - Schedule of Intangible assets (Detail) - USD ($) $ in Thousands | 9 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2024 | Mar. 31, 2024
Finite-Lived Intangible Assets [Line Items] |  |
Intangibles subject to amortization, Gross Carrying Amount | $ 33,000 | $ 33,000
Intangibles subject to amortization, Accumulated Amortization | 8,818 | 7,155
Total intangible amortization | 24,182 | 25,845
Intangibles not subject to amortization, Gross Carrying Amount | 32,220 | 32,220
Intangibles not subject to amortization, Net Carrying Amount | 32,220 | 32,220
Customer Relationships [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Intangibles subject to amortization, Gross Carrying Amount | 16,200 | 16,200
Intangibles subject to amortization, Accumulated Amortization | 2,756 | 1,901
Total intangible amortization | $ 13,444 | $ 14,299
Customer Relationships [Member] | Minimum [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Intangibles subject to amortization, Weighted Average Amortization Period | 8 years | 8 years
Customer Relationships [Member] | Maximum [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Intangibles subject to amortization, Weighted Average Amortization Period | 20 years | 20 years
Technology and Technical Know-How [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Intangibles subject to amortization, Gross Carrying Amount | $ 12,600 | $ 12,600
Intangibles subject to amortization, Accumulated Amortization | 2,101 | 1,535
Total intangible amortization | $ 10,499 | $ 11,065
Technology and Technical Know-How [Member] | Minimum [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Intangibles subject to amortization, Weighted Average Amortization Period | 10 years | 10 years
Technology and Technical Know-How [Member] | Maximum [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Intangibles subject to amortization, Weighted Average Amortization Period | 20 years | 20 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 | 3,844 | 3,677
Total intangible amortization | $ 56 | $ 223
Goodwill [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 | $ 25,520 | $ 25,520
Intangibles not subject to amortization, Net Carrying Amount | $ 25,520 | $ 25,520
Tradename [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Intangibles subject to amortization, Weighted Average Amortization Period | 3 years | 3 years
Intangibles subject to amortization, Gross Carrying Amount | $ 300 | $ 300
Intangibles subject to amortization, Accumulated Amortization | 117 | 42
Total intangible amortization | $ 183 | $ 258
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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