Graham Corporation Quarterly report [Sections 13 or 15(d)]

Quarterly report [Sections 13 or 15(d)]

Cover
- Document and Entity Information
Financial Statements
Notes to Financial Statements
Notes Tables
Notes Details

Equity-Based Compensation - Additional Information (Detail)

v3.25.3

Equity-Based Compensation - Additional Information (Detail) - shares shares in Thousands		3 Months Ended		6 Months Ended
	Aug. 11, 2020	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Performance Vested Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted Stock, Granted		0	0
Time Vesting Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted Stock, Granted		1	0	28	55
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		112
Amended and Restated 2000 Incentive Plan [Member] \| Employee Stock Option [Member]
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		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			88		88

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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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