|
Debt - Additional Information (Detail) (USD $)
|
12 Months Ended | 0 Months Ended | ||
|---|---|---|---|---|
|
Mar. 31, 2015
Contract
|
Mar. 24, 2014
|
Mar. 31, 2014
|
Dec. 03, 2010
|
|
| Debt Instrument [Line Items] | ||||
| Short-term borrowings outstanding | $ 0us-gaap_ShortTermBorrowings | $ 0us-gaap_ShortTermBorrowings | ||
| Long-term debt payment requirements over the next five years | 0us-gaap_LongTermDebt | |||
| Letter of Credit [Member] | ||||
| Debt Instrument [Line Items] | ||||
| Line of credit |
5,000,000us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity / us-gaap_ShortTermDebtTypeAxis = us-gaap_LetterOfCreditMember |
|||
| Revolving credit facility [Member] | ||||
| Debt Instrument [Line Items] | ||||
| Line of credit |
25,000,000us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember |
|||
| Maximum limit of credit facility |
50,000,000us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember |
|||
| Term period of agreement | 3 years | |||
| Number of automatic one year extensions in term period |
2ghm_LineOfCreditFacilityNumberOfExtensionsForMaturityPeriod / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember |
|||
| Term period of agreement, automatic extension | 1 year | |||
| Interest rate description | Interest at either (i) a rate equal to the bank's prime rate; or (ii) a rate equal to LIBOR plus a margin. | |||
| Fix rate to reduce fee on outstanding |
0.55%ghm_FixedRateFeeForSecuredLettersOfCredit / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember |
|||
| Availability under the line of credit |
14,842,000us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember |
|||
| Debt Instrument, Covenant Description | Under the Company's revolving credit facility, the Company covenants to maintain a maximum funded debt to EBITDA ratio, as defined in such credit facility, of 3.5 to 1.0 and a minimum earnings before interest expense and income taxes ("EBIT") to interest ratio, as defined in such credit facility, of 4.0 to 1.0. The agreement also provides that the Company is permitted to pay dividends without limitation if it maintains a funded debt to EBITDA ratio equal to or less than 2.0 to 1.0 and permits the Company to pay dividends in an amount equal to 25% of net income if it maintains a funded debt to EBITDA ratio of greater than 2.0 to 1.0. | |||
| Debt Instrument, Covenant Compliance | The Company was in compliance with all such provisions as of and for the year ended March 31, 2015. | |||
| Percentage of net income to be paid as dividend if EBITDA ratio is greater than 2.0 to 1.0 |
25.00%ghm_DebtCovenantsDividendRestrictionAsPercentageOfConsolidatedNetIncome / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember |
|||
| Assets book value |
111,325,000us-gaap_DebtInstrumentCollateralAmount / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember |
|||
| Revolving credit facility [Member] | Maximum [Member] | ||||
| Debt Instrument [Line Items] | ||||
| Unused commitment fee for borrowing |
0.375%us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_RangeAxis = us-gaap_MaximumMember |
|||
| Fee for outstanding letters of credit |
1.25%ghm_LetterOfCreditCommitmentFeePercentage / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_RangeAxis = us-gaap_MaximumMember |
|||
| Revolving credit facility [Member] | Minimum [Member] | ||||
| Debt Instrument [Line Items] | ||||
| Unused commitment fee for borrowing |
0.20%us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_RangeAxis = us-gaap_MinimumMember |
|||
| Fee for outstanding letters of credit |
0.75%ghm_LetterOfCreditCommitmentFeePercentage / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_RangeAxis = us-gaap_MinimumMember |
|||
| Revolving credit facility [Member] | Dividend Payment Covenant [Member] | Maximum [Member] | ||||
| Debt Instrument [Line Items] | ||||
| Maximum funded debt to EBITDA ratio |
200.00%ghm_MaximumFundedDebtToEarningsBeforeInterestTaxesDepreciationAndAmortizationRatio / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_DividendsAxis = us-gaap_DividendPaidMember / us-gaap_RangeAxis = us-gaap_MaximumMember |
|||
| Revolving credit facility [Member] | Letter of Credit [Member] | ||||
| Debt Instrument [Line Items] | ||||
| Availability under the line of credit |
$ 4,255,000us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_ShortTermDebtTypeAxis = us-gaap_LetterOfCreditMember |
|||
| Maximum funded debt to EBITDA ratio |
350.00%ghm_MaximumFundedDebtToEarningsBeforeInterestTaxesDepreciationAndAmortizationRatio / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_ShortTermDebtTypeAxis = us-gaap_LetterOfCreditMember |
|||
| Annual facility fees |
0.375%us-gaap_LineOfCreditFacilityCommitmentFeePercentage / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_ShortTermDebtTypeAxis = us-gaap_LetterOfCreditMember |
|||
| Minimum earnings to interest ratio |
400.00%ghm_MinimumEarningsBeforeInterestExpenseAndIncomeTaxesToInterestRatio / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_ShortTermDebtTypeAxis = us-gaap_LetterOfCreditMember |
|||
| Revolving credit facility [Member] | Letter of Credit [Member] | Maximum [Member] | ||||
| Debt Instrument [Line Items] | ||||
| Fee for outstanding letters of credit |
1.25%ghm_LetterOfCreditCommitmentFeePercentage / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_RangeAxis = us-gaap_MaximumMember / us-gaap_ShortTermDebtTypeAxis = us-gaap_LetterOfCreditMember |
|||
| Revolving credit facility [Member] | Letter of Credit [Member] | Minimum [Member] | ||||
| Debt Instrument [Line Items] | ||||
| Fee for outstanding letters of credit |
0.75%ghm_LetterOfCreditCommitmentFeePercentage / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_RangeAxis = us-gaap_MinimumMember / us-gaap_ShortTermDebtTypeAxis = us-gaap_LetterOfCreditMember |
|||
| Revolving credit facility [Member] | Prime Rate [Member] | ||||
| Debt Instrument [Line Items] | ||||
| Bank's prime rate |
3.25%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_VariableRateAxis = us-gaap_PrimeRateMember |
3.25%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_VariableRateAxis = us-gaap_PrimeRateMember |
||
| Revolving credit facility [Member] | London Interbank Offered Rate (LIBOR) [Member] | Maximum [Member] | ||||
| Debt Instrument [Line Items] | ||||
| Debt Instrument, Basis Spread on Variable Rate |
2.00%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1 / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_RangeAxis = us-gaap_MaximumMember / us-gaap_VariableRateAxis = us-gaap_LondonInterbankOfferedRateLIBORMember |
|||
| Revolving credit facility [Member] | London Interbank Offered Rate (LIBOR) [Member] | Minimum [Member] | ||||
| Debt Instrument [Line Items] | ||||
| Debt Instrument, Basis Spread on Variable Rate |
1.00%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1 / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_RangeAxis = us-gaap_MinimumMember / us-gaap_VariableRateAxis = us-gaap_LondonInterbankOfferedRateLIBORMember |
| X | ||||||||||
|
- Definition
Debt Covenants Dividend Restriction as Percentage of Consolidated Net Income No definition available.
|
| X | ||||||||||
|
- Definition
The fixed rate fee for outstanding letters of credit that are secured by cash and cash equivalents. No definition available.
|
| X | ||||||||||
|
- Definition
The fee, expressed as a percentage of the standby letter of credit amount, incurred for the issuance of a standby letter of credit. No definition available.
|
| X | ||||||||||
|
- Definition
The term period for each automatic extension of the line of credit facility maturity date. No definition available.
|
| X | ||||||||||
|
- Definition
Line of credit facility number of extensions on line of credit facility before it terminates for maturity period. No definition available.
|
| X | ||||||||||
|
- Definition
The original term period of the line of credit facility. No definition available.
|
| X | ||||||||||
|
- Definition
Maximum funded debt to earnings before interest taxes depreciation and amortization ratio. No definition available.
|
| X | ||||||||||
|
- Definition
Minimum earnings before interest expense and income taxes to interest ratio. No definition available.
|
| X | ||||||||||
|
- Definition
Percentage points added to the reference rate to compute the variable rate on the debt instrument. No definition available.
|
| X | ||||||||||
|
- Definition
Amount of assets pledged to secure a debt instrument. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
|
- Definition
States whether the entity was in compliance with the debt covenants throughout the reporting period, and describes facts and circumstances of any compliance failure. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
|
- Definition
Description of minimum financial levels (for example, tangible net worth and working capital) and achievement of certain financial ratios (for example, working capital ratio and debt service coverage ratio), and adherence to certain clauses which generally require or restrict certain actions (for example, entering into a debt arrangement with equal or greater seniority, and selling or discontinuing a certain business segment or material subsidiary) to be in compliance with the covenant clauses of the debt agreement. May also include a discussion of the adverse consequences that would result if the entity violates or fails to satisfy the covenants. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
|
- Definition
Contractual interest rate for funds borrowed, under the debt agreement. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
|
- Details
|
| X | ||||||||||
|
- Definition
The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used. No definition available.
|
| X | ||||||||||
|
- Definition
Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
|
- Definition
Description of the interest rate for the amounts borrowed under the credit facility, including the terms and the method for determining the interest rate (for example, fixed or variable, LIBOR plus a percentage, increasing rate, timing of interest rate resets, remarketing provisions). Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
|
- Definition
Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
|
- Definition
Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding). Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
|
- Definition
The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility. No definition available.
|
| X | ||||||||||
|
- Definition
Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
|
- Definition
Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
|
- Details
|
| X | ||||||||||
|
- Details
|