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

Acquisition - Schedule of Purchase Price Allocated to Intangible Assets (Detail)

Acquisition - Schedule of Purchase Price Allocated to Intangible Assets (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Customer Relationships [Member]
Business Acquisition [Line Items]
Finite-Lived Intangible Assets, Net	$ 10,718	$ 11,308
Technology and Technical Know-How [Member]
Business Acquisition [Line Items]
Finite-Lived Intangible Assets, Net	9,174	$ 9,679
Barber Nichols Inc [Member]
Business Acquisition [Line Items]
Intangibles subject to amortization, Gross Carrying Amount	25,800
Intangibles subject to amortization, Accumulated Amortization	4,998
Finite-Lived Intangible Assets, Net	$ 20,802
Barber Nichols Inc [Member] \| Customer Relationships [Member]
Business Acquisition [Line Items]
Intangibles subject to amortization, Weighted Average Amortization Period	20 years
Intangibles subject to amortization, Gross Carrying Amount	$ 11,800
Intangibles subject to amortization, Accumulated Amortization	1,082
Finite-Lived Intangible Assets, Net	$ 10,718
Barber Nichols Inc [Member] \| Technology and Technical Know-How [Member]
Business Acquisition [Line Items]
Intangibles subject to amortization, Weighted Average Amortization Period	20 years
Intangibles subject to amortization, Gross Carrying Amount	$ 10,100
Intangibles subject to amortization, Accumulated Amortization	926
Finite-Lived Intangible Assets, Net	$ 9,174
Barber Nichols Inc [Member] \| Backlog [Member]
Business Acquisition [Line Items]
Intangibles subject to amortization, Weighted Average Amortization Period	4 years
Intangibles subject to amortization, Gross Carrying Amount	$ 3,900
Intangibles subject to amortization, Accumulated Amortization	2,990
Finite-Lived Intangible Assets, Net	$ 910
Barber Nichols Inc [Member] \| Tradename [Member]
Business Acquisition [Line Items]
Intangibles not subject to amortization, Weighted Average Amortization Period	Indefinite
Intangibles not subject to amortization, Gross Carrying Amount	$ 6,700
Intangibles not subject to amortization, Net Carrying Amount	$ 6,700