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

Employee Benefit Plans - Summary of Benefit Payments, Which Reflect Future Service, are Expected to be Paid (Detail)

v3.25.1

Employee Benefit Plans - Summary of Benefit Payments, Which Reflect Future Service, are Expected to be Paid (Detail) - Pension Plans, Defined Benefit [Member] $ in Thousands	Mar. 31, 2025 USD ($)
Defined Benefit Plan Disclosure [Line Items]
2026	$ 923
2027	937
2028	1,053
2029	1,121
2030	1,121
2031-2035	8,198
Total	$ 13,353

- Definition

Aggregate amount of benefits from a defined benefit plan expected to be paid in the ten fiscal years following the latest fiscal year.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of benefit for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following current fiscal year.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

+ Details

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- Definition

Amount of benefit for defined benefit plan expected to be paid in next fiscal year following current fiscal year.

+ References

+ Details

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Namespace Prefix:	us-gaap_
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Period Type:	instant

- Definition

Amount of benefit for defined benefit plan expected to be paid in fifth fiscal year following current fiscal year.

+ References

+ Details

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Namespace Prefix:	us-gaap_
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- Definition

Amount of benefit for defined benefit plan expected to be paid in fourth fiscal year following current fiscal year.

+ References

+ Details

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Namespace Prefix:	us-gaap_
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- Definition

Amount of benefit for defined benefit plan expected to be paid in third fiscal year following current fiscal year.

+ References

+ Details

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Namespace Prefix:	us-gaap_
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- Definition

Amount of benefit for defined benefit plan expected to be paid in second fiscal year following current fiscal year.

+ References

+ Details

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Namespace Prefix:	us-gaap_
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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: