Graham Corporation Annual report pursuant to Section 13 and 15(d)

Intangible Assets - Schedule of Intangible assets (Detail)

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