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Retirement Plans and Other Benefits - Asset Allocation (Details) | Dec. 31, 2018
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Pension Benefits |
Defined Benefit Plan Disclosure [Line Items] |
Target Allocation | 100.00%
Actual Allocation | 100.00%
Pension Benefits | Long-term fixed income assets |
Defined Benefit Plan Disclosure [Line Items] |
Target Allocation | 62.00%
Actual Allocation | 64.00%
Pension Benefits | Return-generating assets |
Defined Benefit Plan Disclosure [Line Items] |
Target Allocation | 38.00%
Target Allocation | 38.00%
Actual Allocation | 36.00%
Pension Benefits | Equities in US and other developed markets |
Defined Benefit Plan Disclosure [Line Items] |
Target Allocation | 18.00%
Pension Benefits | Equities in emerging markets |
Defined Benefit Plan Disclosure [Line Items] |
Target Allocation | 6.00%
Pension Benefits | Alternative investments |
Defined Benefit Plan Disclosure [Line Items] |
Target Allocation | 14.00%
Other Benefits |
Defined Benefit Plan Disclosure [Line Items] |
Actual Allocation | 100.00%
Other Benefits | Long-term fixed income assets |
Defined Benefit Plan Disclosure [Line Items] |
Actual Allocation | 69.00%
Other Benefits | Return-generating assets |
Defined Benefit Plan Disclosure [Line Items] |
Actual Allocation | 31.00%

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