v3.26.1
Plan Assets
12 Months Ended
Mar. 31, 2026
EBP 001 [Member]
Plan Assets [Line Items]
Plan Assets
3.
PLAN ASSETS
The Plan’s cash is maintained by the Company on behalf of the Plan.
X
- References
No definition available.
+ Details
Name:
ghm_PlanAssetsLineItems
Namespace Prefix:
ghm_
Data Type:
xbrli:stringItemType
Balance Type:
na
Period Type:
duration
X
- Definition
Plan Assets.
+ References
No definition available.
+ Details
Name:
ghm_PlanAssetsTextBlock
Namespace Prefix:
ghm_
Data Type:
dtr-types:textBlockItemType
Balance Type:
na
Period Type:
duration
X
- Details
Name:
dei_LegalEntityAxis=ghm_EBP001Member
Namespace Prefix:
Data Type:
na
Balance Type:
Period Type: