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Pension Plans and Other Postretirement Benefits (Details 13) - Pension Benefits [Member] | 12 Months Ended
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Dec. 31, 2015
U.S. equities [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target asset allocations range, Minimum | 18.00% |
Target asset allocations range, Maximum | 40.00% |
International equities [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target asset allocations range, Minimum | 7.00% |
Target asset allocations range, Maximum | 17.00% |
Global debt securities and cash [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target asset allocations range, Minimum | 35.00% |
Target asset allocations range, Maximum | 55.00% |
Private equity [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target asset allocations range, Minimum | 0.00% | [1]
Target asset allocations range, Maximum | 10.00% | [1]
Hedge funds [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target asset allocations range, Minimum | 0.00% | [1]
Target asset allocations range, Maximum | 10.00% | [1]
Real estate and other [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target asset allocations range, Minimum | 0.00% | [1]
Target asset allocations range, Maximum | 10.00% | [1]
Private Equity, Hedge Funds, and Real Estate and Other [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target asset allocations range, Minimum | 18.00% |
Target asset allocations range, Maximum | 20.00% |
[1] | Have a combined target allocation of 18% and a 20% limit.

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