Pension and Other Post-Retirement Benefits (Details 11) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011
Expected Subsidies to be received
2012	$ 0.6
2013	0.6
2014	0.6
2015	0.6
2016	0.5
Years 2017-2021	2.8
Total	5.7
Qualified Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
2012	26.0
2013	25.6
2014	25.7
2015	26.1
2016	26.4
Years 2017-2021	133.1
Total	262.9
Nonqualified Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
2012	4.3
2013	4.3
2014	4.4
2015	4.4
2016	4.7
Years 2017-2021	25.7
Total	47.8
Other Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
2012	4.5
2013	4.3
2014	4.2
2015	4.0
2016	3.8
Years 2017-2021	15.5
Total	$ 36.3

Defined benefit plan estimated future benefit payments.

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- Definition

Prescription drug subsidy receipts.

+ References

No definition available.

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- Definition

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).

+ References

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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)

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- Definition

The amount of the benefits expected to be paid in Year 5.

+ References

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- Definition

The amount of the benefits expected to be paid in Year 4.

+ References

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The amount of the benefits expected to be paid in Year 1.

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- Definition

The amount of the benefits expected to be paid in Year 3.

+ References

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- Definition

The amount of the benefits expected to be paid in Year 2.

+ References

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- Definition

Aggregate amount for the next five fiscal years following the first five fiscal years (that is the aggregate of fiscal years six through ten) following the balance sheet date of the prescription drug subsidy receipts expected to be received.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 60

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6414203&loc=d3e39716-114964

Reference 2: 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 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name FASB Staff Position (FSP)

-Number FAS106-2

-Paragraph 22

-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.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

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Amount of the prescription drug subsidy receipts expected to be received in Year 5 after the balance sheet date.

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Amount of the prescription drug subsidy receipts expected to be received in Year 4 after the balance sheet date.

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Amount of the prescription drug subsidy receipts expected to be received in Year 1 after the balance sheet date.

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Amount of the prescription drug subsidy receipts expected to be received in Year 3 after the balance sheet date.

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Amount of the prescription drug subsidy receipts expected to be received in Year 2 after the balance sheet date.

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