Graham Corporation Annual report [Section 13 and 15(d), not S-K Item 405]

Annual report [Section 13 and 15(d), not S-K Item 405]

Cover
- Document and Entity Information
Financial Statements
Notes to Financial Statements
Accounting Policies
- The Company and Its Accounting Policies (Policies)
Notes Tables
Notes Details

Stock Compensation Plans - Additional Information (Detail)

v3.25.1

Stock Compensation Plans - Additional Information (Detail) - USD ($) shares in Thousands, $ in Thousands		12 Months Ended
	Aug. 11, 2020	Mar. 31, 2025
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized stock-based compensation expense		$ 3,148
Weighted average period for recognize expense		1 year 7 months 20 days
Amended and Restated 2000 Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards available for future grants		305
Amended and Restated 2000 Incentive Plan [Member] \| Stock Compensation Prior Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining available shares under equity based compensation plan		112
Amended and Restated 2000 Incentive Plan [Member] \| Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option awards granted	0
Amended and Restated 2000 Incentive Plan [Member] \| Maximum [Member] \| Stock Compensation Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized		722
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum discount on purchase price of common stock percentage on fair market value		15.00%
Common stock may be purchased		400

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The number of shares originally approved that may be purchased by employees under the company employee stock purchase plan.

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