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Income Taxes - Summary of Net Deferred Income Tax Liability (Detail) (USD $)
In Thousands, unless otherwise specified |
Mar. 31, 2015
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Mar. 31, 2014
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| Components of Deferred Tax Assets and Liabilities [Abstract] | ||
| Depreciation | $ (2,196)us-gaap_DeferredTaxLiabilitiesPropertyPlantAndEquipment | $ (2,207)us-gaap_DeferredTaxLiabilitiesPropertyPlantAndEquipment |
| Accrued compensation | 881ghm_DeferredTaxAssetsTaxDeferredExpenseAccruedCompensation | 201ghm_DeferredTaxAssetsTaxDeferredExpenseAccruedCompensation |
| Prepaid pension asset | (465)ghm_DeferredTaxLiabilitiesPrepaidPensionCost | (2,026)ghm_DeferredTaxLiabilitiesPrepaidPensionCost |
| Accrued pension liability | 121us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPensions | 105us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPensions |
| Accrued postretirement benefits | 342us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPostretirementBenefits | 336us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPostretirementBenefits |
| Compensated absences | 629us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsCompensatedAbsences | 584us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsCompensatedAbsences |
| Inventories | (1,042)us-gaap_DeferredTaxLiabilitiesDeferredExpenseCapitalizedInventoryCosts | (101)us-gaap_DeferredTaxLiabilitiesDeferredExpenseCapitalizedInventoryCosts |
| Warranty liability | 231us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsWarrantyReserves | 109us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsWarrantyReserves |
| Accrued expenses | 313us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilities | 329us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilities |
| Stock-based compensation | 500us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost | 419us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost |
| Intangible assets | (5,230)us-gaap_DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets | (5,294)us-gaap_DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets |
| New York State investment tax credit | 952ghm_DeferredTaxAssetsTaxDeferredExpenseStateInvestmentTaxCredit | 738ghm_DeferredTaxAssetsTaxDeferredExpenseStateInvestmentTaxCredit |
| Other | 40ghm_DeferredTaxAssetsLiabilitiesOther | 24ghm_DeferredTaxAssetsLiabilitiesOther |
| Deferred Tax Liabilities, gross | (4,924)us-gaap_DeferredIncomeTaxLiabilities | (6,783)us-gaap_DeferredIncomeTaxLiabilities |
| Less: Valuation allowance | (952)us-gaap_DeferredTaxAssetsValuationAllowance | (738)us-gaap_DeferredTaxAssetsValuationAllowance |
| Total | $ (5,876)us-gaap_DeferredTaxLiabilities | $ (7,521)us-gaap_DeferredTaxLiabilities |
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- Definition
Amount before allocation of valuation allowance of deferred tax asset (liability) attributable to deductible(taxable) temporary differences not separately disclosed. No definition available.
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- Definition
Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from employee benefits and Long Term Incentive Plan. No definition available.
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- Definition
Amount before allocation of valuation allowances of deferred tax asset attributable to deductible state investment tax credit carryforwards. No definition available.
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- Definition
The amount as of the balance sheet date of the estimated future tax effects attributable to the difference between the tax basis of pension liabilities funded in advance and the basis of a prepaid pension asset determined in accordance with generally accepted accounting principles. The difference in basis of such costs will increase future taxable income when such basis difference reverses. Prepaid pension costs represented the cumulative employer's contributions in excess of net pension cost recognized. No definition available.
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- Details
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- Definition
Amount of deferred tax liability attributable to taxable temporary differences. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from compensated absences (includes, but not limited to, sick and personal days). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from pension benefits. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from postretirement benefits. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from share-based compensation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from accrued liabilities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from warranty reserves. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount of deferred tax liability attributable to taxable temporary differences net of deferred tax asset attributable to deductible temporary differences and carryforwards after valuation allowances. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount of deferred tax consequences attributable to taxable temporary differences derived from inventory. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount of deferred tax liability attributable to taxable temporary differences from intangible assets other than goodwill. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount of deferred tax liability attributable to taxable temporary differences from property, plant, and equipment. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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