Pensions and Other Postretirement Benefits - Assumptions Used (Details)	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Pension Benefits
Weighted Average Assumptions:
Discount Rate	4.02%	4.86%	4.20%
Rate of Increase in Future Compensation Levels	1.45%	1.88%	2.03%
Expected Long-Term Rate of Return on Plan Assets	6.81%	7.69%	7.60%
Initial Health Care Cost Trend Rate	0.00%	0.00%	0.00%
Ultimate Health Care Cost Trend Rate	0.00%	0.00%	0.00%
Postretirement Benefits
Weighted Average Assumptions:
Discount Rate	3.95%	4.74%	3.97%
Rate of Increase in Future Compensation Levels	0.00%	0.00%	0.00%
Expected Long-Term Rate of Return on Plan Assets	0.00%	0.00%	0.00%
Initial Health Care Cost Trend Rate	7.38%	7.50%	9.00%
Ultimate Health Care Cost Trend Rate	4.50%	4.96%
DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostUltimateHealthCareCostTrendRate	4.96%	4.77%	4.50%

Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Initial Health Care Cost Trend Rate

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- Definition

DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostUltimateHealthCareCostTrendRate

+ References

No definition available.

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- Definition

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

+ 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 (k)(1)
-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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- Definition

An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 30
-Glossary Expected Long-Term Rate of Return on Plan Assets
-URI http://asc.fasb.org/extlink&oid=6512013

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(3)
-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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- Definition

Expected rate of compensation increases (for pay-related plans).

+ 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 (k)(2)
-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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- 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=35743120&loc=d3e1928-114920

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