Employee Benefit Plans, Weighted-Average Assumptions (Details)	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Minimum [Member]
Employee Benefit Plans (Textual)
Yield curve maturities	6 months
Maximum [Member]
Employee Benefit Plans (Textual)
Yield curve maturities	99 years
Pension Plans [Member]
Weighted Average Assumptions Used to Determine Benefit Obligation
Discount rate	4.45%	4.10%
Rate of compensation increase	3.79%	3.78%
Weighted Average Assumptions Used to Determine Net Periodic Benefit Cost
Discount rate	4.10%	4.92%	4.33%
Expected long-term rate of return on plan assets	7.29%	7.61%	7.62%
Rate of compensation increase	3.78%	3.81%	3.73%
Other Postretirement Benefit Plans [Member]
Weighted Average Assumptions Used to Determine Benefit Obligation
Discount rate	4.53%	4.13%
Rate of compensation increase	0.00%	0.00%
Weighted Average Assumptions Used to Determine Net Periodic Benefit Cost
Discount rate	4.13%	4.88%	4.19%
Expected long-term rate of return on plan assets	0.00%	0.00%	0.00%
Rate of compensation increase	0.00%	0.00%	0.00%

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

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=58740216&loc=d3e1928-114920

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- Definition

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

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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
-Glossary Expected Long-Term Rate of Return on Plan Assets
-URI http://asc.fasb.org/extlink&oid=6512046

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=58740216&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=58740216&loc=d3e1928-114920

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- Definition

Defined benefit plan annualized discount rates range of maturities.

+ References

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- Definition

Employee Benefit Plans, Textual [Abstract]

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