Pension and Other Post-Retirement Benefits (Details 9) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012
Expected Subsidies to be received
2013	$ 0.5
2014	0.5
2015	0.5
2016	0.5
2017	0.4
Years 2018-2022	2.2
Total	4.6
Qualified Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
2013	29.2
2014	29.0
2015	29.0
2016	29.3
2017	31.1
Years 2018-2022	148.3
Total	295.9
Nonqualified Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
2013	2.0
2014	1.9
2015	1.8
2016	2.0
2017	2.0
Years 2018-2022	11.9
Total	21.6
Other Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
2013	4.4
2014	4.3
2015	4.0
2016	3.9
2017	3.6
Years 2018-2022	15.0
Total	$ 35.2

Defined benefit plan estimated future benefit payments.

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Prescription drug subsidy receipts.

+ References

No definition available.

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- Definition

Amount of benefits expected to be paid in the five fiscal years after the fifth fiscal year following the latest fiscal year from a defined benefit plan.

+ References

Reference 1: 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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Amount of benefits expected to be paid in the next fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of benefits expected to be paid in the fifth fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of benefits expected to be paid in the fourth fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of benefits expected to be paid in the third fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of benefits expected to be paid in the second fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of the prescription drug subsidy receipts to be received after the fifth fiscal year following the latest fiscal year.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 60

-Section 50

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

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-Section 50

-Paragraph 1

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Amount of the prescription drug subsidy receipts to be received in the next fiscal year following the latest fiscal year.

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Amount of the prescription drug subsidy receipts to be received in the fifth fiscal year following the latest fiscal year.

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Amount of the prescription drug subsidy receipts to be received in the fourth fiscal year following the latest fiscal year.

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Amount of the prescription drug subsidy receipts to be received in the third fiscal year following the latest fiscal year.

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Amount of the prescription drug subsidy receipts to be received in the second fiscal year following the latest fiscal year.

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