Benefit Plans Benefit Plans (Deferred Compensation Plan) (Details) (USD $) In Millions, unless otherwise specified			12 Months Ended
Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2013 Maximum [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Salary Contribution to Deferred Compensation Plan, Percentage			75.00%
Bonus Contribution to Deferred Compensation Plan, Percentage			100.00%
Deferred Compensation Plan Assets	$ 13.6	$ 11.1
Deferred Compensation Liability, Classified, Noncurrent	$ 13.6	$ 11.1

Deferred Compensation Plan Annual Percentage Bonus Compensation Contribution By Participants

No definition available.

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- Definition

Deferred Compensation Plan Annual Percentage of Salary Contributions to Plan By Participants

+ References

No definition available.

+ Details

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- Details

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- Definition

Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements payable beyond one year (or the operating cycle, if longer).

+ References

No definition available.

+ Details

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- Definition

Carrying amount as of the balance sheet date of assets held under deferred compensation agreements.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.17)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 17

-Article 5

+ Details

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