Employee Benefits - Assumptions Used in Determining Net Periodic Benefit Expense (Details)	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Pension Plans
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount rate	3.85%	4.80%	5.50%
Expected return on plan assets	6.47%	7.50%	8.00%
Rate of compensation increase	3.50%	0.00%	0.00%
Health Care and Life
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount rate	4.18%	0.00%	5.06%
Expected return on plan assets	0.00%	0.00%	0.00%
Rate of compensation increase	3.50%	0.00%	0.00%
Initial trend rate-pre Medicare	8.25%	0.00%	9.40%
Initial trend rate-post Medicare	7.25%	0.00%	9.40%
Ultimate trend rate	5.00%	0.00%	5.00%

Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Initial Trend Rate Post Medicare

No definition available.

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- Definition

Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Initial Trend Rate Pre Medicare

+ References

No definition available.

+ Details

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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=28361610&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=28361610&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=28361610&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=28361610&loc=d3e1928-114920

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