Incentive Compensation Plans (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Performance bonus expense	$ 3,777	$ 3,697	$ 7,388
Profit Share and Savings Plans [Abstract]
Defined contribution plan expense	2,452	2,504	2,639
Pension Plans [Abstract]
Defined benefit plan, contributions	2,973	3,406	3,349
Defined benefit plan, assets	34,229	29,884	25,770
Defined benefit plan, benefit obligation	47,192	48,016	43,110
Defined benefit plan, unfunded status	12,963	18,132	17,340
Share-based compensation expense	6,589	7,712	9,296
Income tax benefit for stock-based compensation arrangments	2,404	2,814	3,417
Fair Value, Inputs, Level 1 [Member] \| Mutual Funds [Member]
Pension Plans [Abstract]
Defined benefit plan, assets	14,803	14,187
Level 2 \| Common Collective Trust [Member]
Pension Plans [Abstract]
Defined benefit plan, assets	$ 19,426	$ 15,697

Performance Bonus Expense

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

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-SubTopic 10

-Section S99

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-Subparagraph (SAB TOPIC 14.F)

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-Name Staff Accounting Bulletin (SAB)

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-Section F

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- Definition

1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date.

+ References

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-Publisher FASB

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-Topic 715

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-Name Accounting Standards Codification

-Glossary Projected Benefit Obligation

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-Glossary Accumulated Postretirement Benefit Obligation

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The increase in the fair value of plan assets from contributions made by the employer.

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Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets.

+ References

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-SubTopic 20

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-Subparagraph (b)

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- Definition

The funded status is measured as the difference between the fair value of plan assets and the benefit obligation. Will normally be the same as the net Defined Benefit Plan, Amounts Recognized in Balance Sheet, Total.

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- Definition

The amount of the cost recognized during the period for defined contribution plans.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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