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

Income Taxes - Additional Information (Detail)

v3.26.1

Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Income Taxes [Line Items]
Valuation allowance	$ 1,086,000	$ 1,048,000
Liability unrecognized tax benefits	0	$ 0
Investment Tax Credit Carryforward [Member]
Income Taxes [Line Items]
Deferred income taxes include the impact of state investment tax credits	292,000
State investment tax credits with an unlimited carryforward period	$ 794,000
International Tax Jurisdictions [Member] \| State Administration of Taxation, China [Member]
Income Taxes [Line Items]
Open tax year	2022 2023 2024 2025
International Tax Jurisdictions [Member] \| Ministry of Finance, India [Member]
Income Taxes [Line Items]
Open tax year	2022 2023 2024 2025
Federal Tax Jurisdictions [Member]
Income Taxes [Line Items]
Open tax year	2022 2023 2024 2025
State Tax Jurisdictions [Member]
Income Taxes [Line Items]
Open tax year	2021 2022 2023 2024 2025
Maximum [Member] \| Investment Tax Credit Carryforward [Member]
Income Taxes [Line Items]
Expiration date of state investment tax credits	Mar. 31, 2040
Minimum [Member] \| Investment Tax Credit Carryforward [Member]
Income Taxes [Line Items]
Expiration date of state investment tax credits	Mar. 31, 2030

- Definition

The amount of deferred income tax assets pertaining to state investment tax credits that have expiration dates.

+ References

No definition available.

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The amount of deferred income tax assets pertaining to state investment tax credits that have an unlimited carryforward period.

+ References

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- Definition

Income taxes.

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- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

+ References

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-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
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Tax year that remains open to examination under enacted tax laws, in YYYY format.

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- Definition

Amount of unrecognized tax benefits.

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