Schedule of Benefit Obligations Weighted Average Assumptions [Line Items]

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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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Employee Retirement Benefits (Weighted-Average Assumptions Used) (Details)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Benefit Obligations \| Pension Plan
Schedule of Benefit Obligations Weighted Average Assumptions
Discount rate	4.55%	4.25%
Benefit Obligations \| Pension Plan \| Minimum
Schedule of Benefit Obligations Weighted Average Assumptions
Rate of compensation increase	2.75%	2.75%
Benefit Obligations \| Pension Plan \| Maximum
Schedule of Benefit Obligations Weighted Average Assumptions
Rate of compensation increase	3.25%	3.25%
Benefit Obligations \| Supplemental Employee Retirement Plan
Schedule of Benefit Obligations Weighted Average Assumptions
Discount rate	4.30%	4.05%
Benefit Obligations \| Supplemental Employee Retirement Plan \| Minimum
Schedule of Benefit Obligations Weighted Average Assumptions
Rate of compensation increase	2.75%	2.75%
Benefit Obligations \| Supplemental Employee Retirement Plan \| Maximum
Schedule of Benefit Obligations Weighted Average Assumptions
Rate of compensation increase	3.25%	3.25%
Net Periodic Benefit Cost \| Pension Plan
Schedule of Benefit Obligations Weighted Average Assumptions
Discount rate	4.25%	5.15%	4.20%
Expected return on plan assets	7.25%	7.25%	7.50%
Net Periodic Benefit Cost \| Pension Plan \| Minimum
Schedule of Benefit Obligations Weighted Average Assumptions
Rate of compensation increase	2.75%	2.75%	2.75%
Net Periodic Benefit Cost \| Pension Plan \| Maximum
Schedule of Benefit Obligations Weighted Average Assumptions
Rate of compensation increase	3.25%	3.25%	3.25%
Net Periodic Benefit Cost \| Supplemental Employee Retirement Plan
Schedule of Benefit Obligations Weighted Average Assumptions
Discount rate	4.05%	4.80%	3.95%
Net Periodic Benefit Cost \| Supplemental Employee Retirement Plan \| Minimum
Schedule of Benefit Obligations Weighted Average Assumptions
Rate of compensation increase	2.75%	2.75%	2.75%
Net Periodic Benefit Cost \| Supplemental Employee Retirement Plan \| Maximum
Schedule of Benefit Obligations Weighted Average Assumptions
Rate of compensation increase	3.25%	3.25%	3.25%