Pensions and Postretirement Benefits Other Than Pensions (Schedule of Defined Benefit Plan Weighted Average Discount Rate Assumptions) (Details) - Postretirement [Member]	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Discount rate	3.50%	3.50%	3.50%
Net periodic benefit cost	3.50%	3.50%	4.00%
Year that the rate reaches the ultimate trend rate			2021
current year medical inflation [Member]
Defined Benefit Plan, Ultimate Health Care Cost Trend Rate	0.00%	0.00%	7.25%
ultimate inflation rate [Member]
Defined Benefit Plan, Ultimate Health Care Cost Trend Rate	0.00%	0.00%	5.00%

The interest rate used to adjust for the time value of money for the plan.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(1)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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- Definition

The interest rate used to adjust for the time value of money.

+ References

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Period Type:	duration

- Definition

The ultimate trend rate for health care costs.

+ 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 (l)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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- Definition

Year the ultimate health care cost trend rate is expected to be reached, in CCYY format.

+ 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 (l)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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