Fair Value Measurements (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Assets Held For Sale [Abstract]
Carrying value of assets held-for-sale	$ 11.6	$ 11.4
U.S. Pension Plans [Member]
U.S. pension plan assets [Abstract]
Fair value of plan assets	213.7	200.6
Money Market Investments [Member] \| U.S. Pension Plans [Member]
U.S. pension plan assets [Abstract]
Fair value of plan assets	11.3	7.3
Common Stock [Member] \| U.S. Pension Plans [Member]
U.S. pension plan assets [Abstract]
Fair value of plan assets	42.2	36.0
Corporate Bonds [Member] \| U.S. Pension Plans [Member]
U.S. pension plan assets [Abstract]
Fair value of plan assets	21.3	19.1
Pooled Equity Funds [Member] \| U.S. Pension Plans [Member]
U.S. pension plan assets [Abstract]
Fair value of plan assets	80.8	82.9
Pooled Fixed Income Funds [Member] \| U.S. Pension Plans [Member]
U.S. pension plan assets [Abstract]
Fair value of plan assets	14.1	17.6
US Government and Agency Securities [Member] \| U.S. Pension Plans [Member]
U.S. pension plan assets [Abstract]
Fair value of plan assets	37.0	32.1
Other [Member] \| U.S. Pension Plans [Member]
U.S. pension plan assets [Abstract]
Fair value of plan assets	7.0	5.6
Level 1 [Member] \| U.S. Pension Plans [Member]
U.S. pension plan assets [Abstract]
Fair value of plan assets	124.7	123.3
Level 1 [Member] \| Money Market Investments [Member] \| U.S. Pension Plans [Member]
U.S. pension plan assets [Abstract]
Fair value of plan assets	0	0
Level 1 [Member] \| Common Stock [Member] \| U.S. Pension Plans [Member]
U.S. pension plan assets [Abstract]
Fair value of plan assets	40.1	35.9
Level 1 [Member] \| Corporate Bonds [Member] \| U.S. Pension Plans [Member]
U.S. pension plan assets [Abstract]
Fair value of plan assets	0	0
Level 1 [Member] \| Pooled Equity Funds [Member] \| U.S. Pension Plans [Member]
U.S. pension plan assets [Abstract]
Fair value of plan assets	68.9	68.8
Level 1 [Member] \| Pooled Fixed Income Funds [Member] \| U.S. Pension Plans [Member]
U.S. pension plan assets [Abstract]
Fair value of plan assets	14.1	17.6
Level 1 [Member] \| US Government and Agency Securities [Member] \| U.S. Pension Plans [Member]
U.S. pension plan assets [Abstract]
Fair value of plan assets	0	0
Level 1 [Member] \| Other [Member] \| U.S. Pension Plans [Member]
U.S. pension plan assets [Abstract]
Fair value of plan assets	1.6	1.0
Level 2 [Member] \| U.S. Pension Plans [Member]
U.S. pension plan assets [Abstract]
Fair value of plan assets	89.0	77.3
Level 2 [Member] \| Money Market Investments [Member] \| U.S. Pension Plans [Member]
U.S. pension plan assets [Abstract]
Fair value of plan assets	11.3	7.3
Level 2 [Member] \| Common Stock [Member] \| U.S. Pension Plans [Member]
U.S. pension plan assets [Abstract]
Fair value of plan assets	2.1	0.1
Level 2 [Member] \| Corporate Bonds [Member] \| U.S. Pension Plans [Member]
U.S. pension plan assets [Abstract]
Fair value of plan assets	21.3	19.1
Level 2 [Member] \| Pooled Equity Funds [Member] \| U.S. Pension Plans [Member]
U.S. pension plan assets [Abstract]
Fair value of plan assets	11.9	14.1
Level 2 [Member] \| Pooled Fixed Income Funds [Member] \| U.S. Pension Plans [Member]
U.S. pension plan assets [Abstract]
Fair value of plan assets	0	0
Level 2 [Member] \| US Government and Agency Securities [Member] \| U.S. Pension Plans [Member]
U.S. pension plan assets [Abstract]
Fair value of plan assets	37.0	32.1
Level 2 [Member] \| Other [Member] \| U.S. Pension Plans [Member]
U.S. pension plan assets [Abstract]
Fair value of plan assets	5.4	4.6
Level 3 [Member] \| U.S. Pension Plans [Member]
U.S. pension plan assets [Abstract]
Fair value of plan assets	0	0
Level 3 [Member] \| Money Market Investments [Member] \| U.S. Pension Plans [Member]
U.S. pension plan assets [Abstract]
Fair value of plan assets	0	0
Level 3 [Member] \| Common Stock [Member] \| U.S. Pension Plans [Member]
U.S. pension plan assets [Abstract]
Fair value of plan assets	0	0
Level 3 [Member] \| Corporate Bonds [Member] \| U.S. Pension Plans [Member]
U.S. pension plan assets [Abstract]
Fair value of plan assets	0	0
Level 3 [Member] \| Pooled Equity Funds [Member] \| U.S. Pension Plans [Member]
U.S. pension plan assets [Abstract]
Fair value of plan assets	0	0
Level 3 [Member] \| Pooled Fixed Income Funds [Member] \| U.S. Pension Plans [Member]
U.S. pension plan assets [Abstract]
Fair value of plan assets	0	0
Level 3 [Member] \| US Government and Agency Securities [Member] \| U.S. Pension Plans [Member]
U.S. pension plan assets [Abstract]
Fair value of plan assets	0	0
Level 3 [Member] \| Other [Member] \| U.S. Pension Plans [Member]
U.S. pension plan assets [Abstract]
Fair value of plan assets	0	0
Fair Value, Measurements, Recurring [Member]
Assets [Abstract]
Trading securities	2.6	2.3
Total assets	2.6	2.3
Liabilities [Abstract]
Derivative financial instruments	0.4	1.4
Deferred compensation obligations	2.6	2.3
Total liabilities	3.0	3.7
Fair Value, Measurements, Recurring [Member] \| Level 1 [Member]
Assets [Abstract]
Trading securities	2.6	2.3
Total assets	2.6	2.3
Liabilities [Abstract]
Derivative financial instruments	0	0
Deferred compensation obligations	2.6	2.3
Total liabilities	2.6	2.3
Fair Value, Measurements, Recurring [Member] \| Level 2 [Member]
Assets [Abstract]
Trading securities	0	0
Total assets	0	0
Liabilities [Abstract]
Derivative financial instruments	0.4	1.4
Deferred compensation obligations	0	0
Total liabilities	0.4	1.4
Fair Value, Measurements, Recurring [Member] \| Level 3 [Member]
Assets [Abstract]
Trading securities	0	0
Total assets	0	0
Liabilities [Abstract]
Derivative financial instruments	0	0
Deferred compensation obligations	0	0
Total liabilities	$ 0	$ 0

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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.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value of obligations measured on a recurring basis.

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Amount of investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

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