Employee Benefit Plans (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Postemployment Benefits [Abstract]
Service cost for benefits earned during the period	$ 827us-gaap_DefinedBenefitPlanServiceCost	$ 726us-gaap_DefinedBenefitPlanServiceCost	$ 622us-gaap_DefinedBenefitPlanServiceCost
Interest cost on accumulated postretirement benefit	720us-gaap_DefinedBenefitPlanInterestCost	564us-gaap_DefinedBenefitPlanInterestCost	554us-gaap_DefinedBenefitPlanInterestCost
Other components	14us-gaap_DefinedBenefitPlanOtherCosts	19us-gaap_DefinedBenefitPlanOtherCosts	4us-gaap_DefinedBenefitPlanOtherCosts
Net periodic postretirement benefit cost	$ 1,561	$ 1,309	$ 1,180

The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.

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- Definition

The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.

+ References

+ Details

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- Definition

Amount of other defined benefit plan costs.

+ References

No definition available.

+ Details

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- Definition

The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (h)(1)

-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Service Cost (Component of Net Periodic Pension Cost)

-URI http://asc.fasb.org/extlink&oid=6525008

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

+ Details

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- Details

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