Pension Plans and Other Postretirement Benefits (Details 14) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014
Pension Benefits [Member]
Defined Benefit Plan Expected Future Benefit Payments [Abstract]
2015	$ 195.4
2016	195.4
2017	195.1
2018	195.4
2019	195.1
2020-2024	967.7
Other Postretirement Benefits [Member]
Defined Benefit Plan Expected Future Benefit Payments [Abstract]
2015	51.3
2016	44.7
2017	42.6
2018	40.4
2019	38.3
2020-2024	154.7
Medicare Part D Subsidy [Abstract]
2015	1.1
2016	1.1
2017	1.1
2018	1.1
2019	1.1
2020-2024	$ 4.7

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Amount of benefits from a defined benefit plan expected to be paid in the five fiscal years after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of benefits from a defined benefit plan expected to be paid in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of benefits from a defined benefit plan expected to be paid in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of benefits from a defined benefit plan expected to be paid in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of benefits from a defined benefit plan expected to be paid in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of benefits from a defined benefit plan expected to be paid in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of the prescription drug subsidy receipts to be received after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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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)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

Reference 2: 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

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Amount of the prescription drug subsidy receipts to be received in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of the prescription drug subsidy receipts to be received in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of the prescription drug subsidy receipts to be received in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of the prescription drug subsidy receipts to be received in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of the prescription drug subsidy receipts to be received in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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