Employee Benefit Plans Employee Benefit Plans (Expected Future Minimum Payments) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011
Pension Benefits [Member]
Aggregate expected benefit payments
2012	$ 47.1
2013	45.9
2014	49.0
2015	50.2
2016	46.5
2017 through 2021	248.6
Total	487.3
Postretirement Benefits [Member]
Aggregate expected benefit payments
2012	1.9
2013	2.1
2014	2.1
2015	2.1
2016	2.2
2017 through 2021	11.5
Total	21.9
ENPP [Member]
Aggregate expected benefit payments
2012	1.0
2013	1.3
2014	1.3
2015	0.9
2016	1.1
2017 through 2021	13.6
Total	$ 19.2

The amount of the aggregate benefits expected to be paid in the five fiscal years thereafter (the aggregate amount of benefits expected to be paid in years 6 through 10 after the date of the latest statement of financial position).

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph f

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (f)

-URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e1928-114920

Name:	us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsInFiveFiscalYearsThereafter
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant