Retirement Benefits (Details 14) $ in Millions	Dec. 31, 2016 USD ($)
Pension Benefits [Member]
Defined Benefit Plan Expected Future Benefit Payments [Abstract]
2017	$ 194.7
2018	191.8
2019	189.6
2020	188.3
2021	186.5
2022-2026	901.5
Other Postretirement Benefits [Member]
Defined Benefit Plan Expected Future Benefit Payments [Abstract]
2017	37.1
2018	35.1
2019	32.6
2020	30.6
2021	29.1
2022-2026	121.8
Medicare Part D Subsidy [Abstract]
2017	1.0
2018	1.0
2019	0.9
2020	0.9
2021	0.8
2022-2026	$ 3.5

Defined Benefit Plan Expected Future Benefit Payments [Abstract]

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 60
-Section 50
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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-SubTopic 20
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-Paragraph 1
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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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