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Employee Benefit Plans - Additional Information (Detail) (USD $)
In Thousands, unless otherwise specified |
9 Months Ended | |
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Dec. 31, 2014
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Mar. 31, 2014
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| Defined Benefit Plan Disclosure [Line Items] | ||
| Self-Insured medical plan liability | $ 300ghm_SelfInsuredMedicalPlanLiability | $ 221ghm_SelfInsuredMedicalPlanLiability |
| Pension Plans, Defined Benefit [Member] | ||
| Defined Benefit Plan Disclosure [Line Items] | ||
| Contributions to its defined benefit pension plan |
55us-gaap_DefinedBenefitPlanContributionsByEmployer / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |
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| Contributions to the plan for the fiscal 2015 |
0us-gaap_DefinedBenefitPlansEstimatedFutureEmployerContributionsInCurrentFiscalYear / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |
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| Other Postretirement Benefit Plans [Member] | ||
| Defined Benefit Plan Disclosure [Line Items] | ||
| Post retirement benefit plan |
2us-gaap_DefinedBenefitPlanBenefitsPaid / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember |
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| Defined benefit plan, benefit expected to pay |
$ 96us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsRemainderOfFiscalYear / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember |
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- Definition
The liability recognized in the balance sheet that is associated with the self insured medical plan. No definition available.
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- Definition
The amount of payments made for which participants are entitled under a pension plan, including pension benefits, death benefits, and benefits due on termination of employment. Also includes payments made under a postretirement benefit plan, including prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. This item represents a periodic decrease to the plan obligations and a decrease to plan assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The increase in the fair value of plan assets from contributions made by the employer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Definition
Amount of benefits from a defined benefit plan expected to be paid in the remainder of the fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. No definition available.
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- Definition
Amount of employer's best estimate of contributions expected to be paid to the plan in the current remaining fiscal period. No definition available.
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- Details
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- Details
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