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Retirement Benefits (Details 13) - Pension Benefits [Member] | 12 Months Ended
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Dec. 31, 2016
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 | 10.00%
Target asset allocations range, Maximum | 30.00%
Global debt securities and cash [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target asset allocations range, Minimum | 15.00%
Target asset allocations range, Maximum | 40.00%
Private equity [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target asset allocations range, Minimum | 0.00%
Target asset allocations range, Maximum | 15.00%
Hedge funds [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target asset allocations range, Minimum | 10.00%
Target asset allocations range, Maximum | 20.00%
Real estate and other [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target asset allocations range, Minimum | 0.00%
Target asset allocations range, Maximum | 10.00%

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- Definition Target allocation maximum percentage of investments of this type to total plan assets presented on a weighted average basis. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (c)(i) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e2446-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(i) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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