Postretirement Benefits Contributions, Benefit Payments and Other (Details) - USD ($) $ in Millions |
Dec. 31, 2017 |
Dec. 31, 2016 |
|---|---|---|
| Expected Benefit Payments [Abstract] | ||
| Defined Benefit Plan Estimated Future Employer Required Contributions In Next Fiscal Year Qualified Plan | $ 70.0 | |
| Defined Benefit Plan Estimated Future Employer Contributions In Next Fiscal Year Unfunded Plan | 3.8 | |
| Pension Plans [Member] | ||
| Defined Benefit Plan Disclosure [Line Items] | ||
| Defined Benefit Plan, Accumulated Benefit Obligation | 716.9 | $ 921.5 |
| Expected Benefit Payments [Abstract] | ||
| Company Contributions Expected to be Made in 2017 | 73.8 | |
| 2018 | 44.4 | |
| 2019 | 45.0 | |
| 2020 | 45.3 | |
| 2021 | 45.1 | |
| 2022 | 45.1 | |
| 2023-2027 | 221.6 | |
| Other Postretirement Benefit Plans [Member] | ||
| Expected Benefit Payments [Abstract] | ||
| Company Contributions Expected to be Made in 2017 | 3.7 | |
| 2018 | 3.7 | |
| 2019 | 3.6 | |
| 2020 | 3.4 | |
| 2021 | 3.1 | |
| 2022 | 2.9 | |
| 2023-2027 | $ 12.6 |
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- Definition The employer's best estimate, as soon as it can be reasonably determined, of required contributions expected to be paid to the unqualified plan during the next fiscal year beginning after the date of the latest statement of financial position. No definition available.
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- Definition The employer's best estimate, as soon as it can be reasonably determined, of required contributions expected to be paid to the qualified plan during the next fiscal year beginning after the date of the latest statement of financial position. No definition available.
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- Definition Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- References No definition available.
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- Definition Amount of benefits for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of benefits for defined benefit plan expected to be paid in next fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of benefits for defined benefit plan expected to be paid in fifth fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of benefits for defined benefit plan expected to be paid in fourth fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of benefits for defined benefit plan expected to be paid in third fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of benefits for defined benefit plan expected to be paid in second fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of contributions expected to be received by defined benefit plan from employer in next fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Details
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