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

Annual report pursuant to Section 13 and 15(d)

Subsequent Events - Additional Information (Detail)

Subsequent Events - Additional Information (Detail) - USD ($) shares in Thousands, $ in Thousands		12 Months Ended
	Jun. 01, 2021	Mar. 31, 2020	Dec. 02, 2020	Oct. 08, 2020	May 01, 2020
HSBC Bank USA [Member] \| Letter of Credit [Member]
Subsequent Event [Line Items]
Line of credit		$ 10,000		$ 15,000	$ 14,000
Letter of Credit [Member]
Subsequent Event [Line Items]
Line of credit			$ 7,000
Revolving Credit Facility [Member] \| HSBC Bank USA [Member] \| Letter of Credit [Member]
Subsequent Event [Line Items]
Debt instrument, basis spread on variable rate		3.00%
Annual facility fee		$ 5
Maximum [Member] \| Revolving Credit Facility [Member] \| HSBC Bank USA [Member] \| Letter of Credit [Member]
Subsequent Event [Line Items]
Fee for outstanding letters of credit		0.85%
Minimum [Member] \| Revolving Credit Facility [Member] \| HSBC Bank USA [Member] \| Letter of Credit [Member]
Subsequent Event [Line Items]
Fee for outstanding letters of credit		0.75%
Subsequent Event [Member] \| Revolving Credit Facility [Member] \| Letter of Credit [Member]
Subsequent Event [Line Items]
Debt instrument, basis spread on variable rate	3.00%
Annual facility fee	$ 5
Subsequent Event [Member] \| Maximum [Member] \| HSBC Bank USA [Member] \| Letter of Credit [Member]
Subsequent Event [Line Items]
Line of credit	$ 15,000
Subsequent Event [Member] \| Maximum [Member] \| Revolving Credit Facility [Member] \| Letter of Credit [Member]
Subsequent Event [Line Items]
Fee for outstanding letters of credit	0.85%
Subsequent Event [Member] \| Minimum [Member] \| HSBC Bank USA [Member] \| Letter of Credit [Member]
Subsequent Event [Line Items]
Line of credit	$ 7,500
Subsequent Event [Member] \| Minimum [Member] \| Revolving Credit Facility [Member] \| Letter of Credit [Member]
Subsequent Event [Line Items]
Fee for outstanding letters of credit	0.75%
Barber-Nichols, Inc. [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Business combination, purchase price	$ 70,113
Business combination, common stock, shares	610
Business combination, common stock value	$ 8,963
Business combination, cash consideration	61,150
Term loan payment	$ 20,000
Term loan payment period	5 years
Term loan principal payment frequency	monthly
Term loan principal payment	$ 167
Remaining principal amount maturity date	Jun. 01, 2026
Percentage of upfront fees	0.20%
Unused commitment fee for borrowing	0.25%
Maximum leverage ratio	3.0
Minimum fixed charge coverage ratio	1.20
Percentage of minimum margined assets on outstanding facility	100.00%
Barber-Nichols, Inc. [Member] \| Subsequent Event [Member] \| Line of Credit [Member]
Subsequent Event [Line Items]
Line of credit	$ 30,000
Maximum limit of credit facility	$ 40,000
Barber-Nichols, Inc. [Member] \| Subsequent Event [Member] \| Letter of Credit [Member]
Subsequent Event [Line Items]
Fee for outstanding letters of credit	1.50%
Barber-Nichols, Inc. [Member] \| Subsequent Event [Member] \| BSBY [Member]
Subsequent Event [Line Items]
Debt instrument, basis spread on variable rate	1.50%
Barber-Nichols, Inc. [Member] \| Subsequent Event [Member] \| BSBY [Member] \| Line of Credit [Member]
Subsequent Event [Line Items]
Debt instrument, basis spread on variable rate	1.50%
Barber-Nichols, Inc. [Member] \| Subsequent Event [Member] \| Floor Rate [Member]
Subsequent Event [Line Items]
Debt instrument, basis spread on variable rate	0.00%
Barber-Nichols, Inc. [Member] \| Subsequent Event [Member] \| Floor Rate [Member] \| Line of Credit [Member]
Subsequent Event [Line Items]
Debt instrument, basis spread on variable rate	0.00%
Barber-Nichols, Inc. [Member] \| Subsequent Event [Member] \| Maximum [Member]
Subsequent Event [Line Items]
Business combination contingent earn-out eligible to receive, additional cash consideration	$ 14,000