Income Taxes - Schedule of Current and Deferred Income Tax Liabilities (Details) (USD $) In Millions	Sep. 30, 2011	Dec. 31, 2010
Income Tax Disclosure [Abstract]
Deferred Income Tax Liabilities	$ 63.1	$ 7.3
Unrecognized Tax Benefits	6.1	7.8
Liabilities for Income Taxes	$ 69.2	$ 15.1

The cumulative amount for all deferred tax liabilities as of the balance sheet date arising from temporary differences between accounting income in accordance with generally accepted accounting principles and tax-basis income that will result in future taxable income exceeding future accounting income.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 7

-Section 03

-Paragraph 15

-Subparagraph b(2)

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 109

-Paragraph 43, 289

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Deferred Tax Liability

-URI http://asc.fasb.org/extlink&oid=6510232

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32537-109319

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Balance Type:	credit
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