Income Taxes (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Jun. 30, 2011	Jun. 30, 2010
Income Taxes (Textuals) [Abstract]
Income tax expense	$ 17.8	$ 9.8
Effective tax rate	15.70%	9.60%
United States federal statutory rate	35.00%
Overall effect of foreign tax rates on effective tax rate	12.00%	10.70%
Prior years' impact of discrete net tax benefits on effective tax rate	5.50%	13.70%
Discrete tax benefits associated with tax authority settlement	$ 6.2	$ 14.0

Income Taxes.

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- Definition

A ratio calculated by dividing the reported amount of income tax expense attributable to continuing operations for the period by GAAP-basis pretax income from continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 109
-Paragraph 47

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 08
-Paragraph h
-Subparagraph 2
-Article 4

+ Details

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- Definition

The domestic federal statutory tax rate applicable under enacted tax laws to the Company's pretax income from continuing operations for the period. The "statutory" tax rate shall be the regular tax rate if there are alternative tax systems.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 109
-Paragraph 47

+ Details

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- Definition

The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate that can be explained by the difference between statutory income tax rates in foreign jurisdictions and the domestic federal statutory income tax rate recorded during the period.

+ Details

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- Definition

The sum of the differences between the effective income tax rate and domestic federal statutory income tax rate attributable to all income tax settlements during the period.

+ Details

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- Definition

The sum of the current income tax expense (benefit) and the deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 08
-Paragraph h
-Article 4

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 109
-Paragraph 45
-Subparagraph a, b

+ Details

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- Definition

The sum of the differences between total income tax expense (benefit) as reported in the Income Statement and the expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to all income tax settlements for the period.

+ Details

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