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Retirement Benefits (Details 13) - Pension Benefits [Member]	12 Months Ended
	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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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

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Target allocation minimum 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 1
-Subparagraph (d)(i)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

Reference 2: 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

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