Schedule II - Valuation and Qualifying Accounts (Detail) (USD $)
In Thousands, unless otherwise specified |
12 Months Ended | ||
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Mar. 31, 2015
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Mar. 31, 2014
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Mar. 31, 2013
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Reserve for Doubtful Accounts Receivable [Member] | |||
Valuation and Qualifying Accounts Disclosure [Line Items] | |||
Balance at Beginning of Period |
$ 46us-gaap_ValuationAllowancesAndReservesBalance / us-gaap_ValuationAllowancesAndReservesTypeAxis = us-gaap_AllowanceForDoubtfulAccountsMember |
$ 33us-gaap_ValuationAllowancesAndReservesBalance / us-gaap_ValuationAllowancesAndReservesTypeAxis = us-gaap_AllowanceForDoubtfulAccountsMember |
$ 43us-gaap_ValuationAllowancesAndReservesBalance / us-gaap_ValuationAllowancesAndReservesTypeAxis = us-gaap_AllowanceForDoubtfulAccountsMember |
Charged to Costs and Expenses |
24us-gaap_ValuationAllowancesAndReservesChargedToCostAndExpense / us-gaap_ValuationAllowancesAndReservesTypeAxis = us-gaap_AllowanceForDoubtfulAccountsMember |
19us-gaap_ValuationAllowancesAndReservesChargedToCostAndExpense / us-gaap_ValuationAllowancesAndReservesTypeAxis = us-gaap_AllowanceForDoubtfulAccountsMember |
(10)us-gaap_ValuationAllowancesAndReservesChargedToCostAndExpense / us-gaap_ValuationAllowancesAndReservesTypeAxis = us-gaap_AllowanceForDoubtfulAccountsMember |
Charged to Other Accounts |
0us-gaap_ValuationAllowancesAndReservesChargedToOtherAccounts / us-gaap_ValuationAllowancesAndReservesTypeAxis = us-gaap_AllowanceForDoubtfulAccountsMember |
0us-gaap_ValuationAllowancesAndReservesChargedToOtherAccounts / us-gaap_ValuationAllowancesAndReservesTypeAxis = us-gaap_AllowanceForDoubtfulAccountsMember |
0us-gaap_ValuationAllowancesAndReservesChargedToOtherAccounts / us-gaap_ValuationAllowancesAndReservesTypeAxis = us-gaap_AllowanceForDoubtfulAccountsMember |
Deductions |
(8)us-gaap_ValuationAllowancesAndReservesDeductions / us-gaap_ValuationAllowancesAndReservesTypeAxis = us-gaap_AllowanceForDoubtfulAccountsMember |
(6)us-gaap_ValuationAllowancesAndReservesDeductions / us-gaap_ValuationAllowancesAndReservesTypeAxis = us-gaap_AllowanceForDoubtfulAccountsMember |
|
Balance at End of Period |
62us-gaap_ValuationAllowancesAndReservesBalance / us-gaap_ValuationAllowancesAndReservesTypeAxis = us-gaap_AllowanceForDoubtfulAccountsMember |
46us-gaap_ValuationAllowancesAndReservesBalance / us-gaap_ValuationAllowancesAndReservesTypeAxis = us-gaap_AllowanceForDoubtfulAccountsMember |
33us-gaap_ValuationAllowancesAndReservesBalance / us-gaap_ValuationAllowancesAndReservesTypeAxis = us-gaap_AllowanceForDoubtfulAccountsMember |
Product Warranty Liability [Member] | |||
Valuation and Qualifying Accounts Disclosure [Line Items] | |||
Balance at Beginning of Period |
308us-gaap_ValuationAllowancesAndReservesBalance / us-gaap_ValuationAllowancesAndReservesTypeAxis = us-gaap_WarrantyReservesMember |
408us-gaap_ValuationAllowancesAndReservesBalance / us-gaap_ValuationAllowancesAndReservesTypeAxis = us-gaap_WarrantyReservesMember |
215us-gaap_ValuationAllowancesAndReservesBalance / us-gaap_ValuationAllowancesAndReservesTypeAxis = us-gaap_WarrantyReservesMember |
Charged to Costs and Expenses |
930us-gaap_ValuationAllowancesAndReservesChargedToCostAndExpense / us-gaap_ValuationAllowancesAndReservesTypeAxis = us-gaap_WarrantyReservesMember |
125us-gaap_ValuationAllowancesAndReservesChargedToCostAndExpense / us-gaap_ValuationAllowancesAndReservesTypeAxis = us-gaap_WarrantyReservesMember |
360us-gaap_ValuationAllowancesAndReservesChargedToCostAndExpense / us-gaap_ValuationAllowancesAndReservesTypeAxis = us-gaap_WarrantyReservesMember |
Charged to Other Accounts |
0us-gaap_ValuationAllowancesAndReservesChargedToOtherAccounts / us-gaap_ValuationAllowancesAndReservesTypeAxis = us-gaap_WarrantyReservesMember |
0us-gaap_ValuationAllowancesAndReservesChargedToOtherAccounts / us-gaap_ValuationAllowancesAndReservesTypeAxis = us-gaap_WarrantyReservesMember |
0us-gaap_ValuationAllowancesAndReservesChargedToOtherAccounts / us-gaap_ValuationAllowancesAndReservesTypeAxis = us-gaap_WarrantyReservesMember |
Deductions |
(585)us-gaap_ValuationAllowancesAndReservesDeductions / us-gaap_ValuationAllowancesAndReservesTypeAxis = us-gaap_WarrantyReservesMember |
(225)us-gaap_ValuationAllowancesAndReservesDeductions / us-gaap_ValuationAllowancesAndReservesTypeAxis = us-gaap_WarrantyReservesMember |
(167)us-gaap_ValuationAllowancesAndReservesDeductions / us-gaap_ValuationAllowancesAndReservesTypeAxis = us-gaap_WarrantyReservesMember |
Balance at End of Period |
653us-gaap_ValuationAllowancesAndReservesBalance / us-gaap_ValuationAllowancesAndReservesTypeAxis = us-gaap_WarrantyReservesMember |
308us-gaap_ValuationAllowancesAndReservesBalance / us-gaap_ValuationAllowancesAndReservesTypeAxis = us-gaap_WarrantyReservesMember |
408us-gaap_ValuationAllowancesAndReservesBalance / us-gaap_ValuationAllowancesAndReservesTypeAxis = us-gaap_WarrantyReservesMember |
Restructuring Reserve [Member] | |||
Valuation and Qualifying Accounts Disclosure [Line Items] | |||
Charged to Costs and Expenses |
1,718us-gaap_ValuationAllowancesAndReservesChargedToCostAndExpense / us-gaap_ValuationAllowancesAndReservesTypeAxis = ghm_RestructuringReserveMember |
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Charged to Other Accounts |
0us-gaap_ValuationAllowancesAndReservesChargedToOtherAccounts / us-gaap_ValuationAllowancesAndReservesTypeAxis = ghm_RestructuringReserveMember |
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Balance at End of Period |
$ 1,718us-gaap_ValuationAllowancesAndReservesBalance / us-gaap_ValuationAllowancesAndReservesTypeAxis = ghm_RestructuringReserveMember |
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- Definition
Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs, charged to costs and expenses. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs, charged to accounts other than costs and expenses in a given period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Total of the deductions in a given period to allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs, representing receivables written off as uncollectible and portions of the reserves utilized, respectively. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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