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Pension and Other Postretirement Benefits Employer contributions (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended	1 Months Ended	12 Months Ended	45 Months Ended
	Dec. 31, 2013	Jun. 30, 2011 SERB plan [Member]	Dec. 31, 2013 PBGC Agreement [Member]	Dec. 31, 2016 PBGC Agreement [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Employer contributions	$ 11,130	$ 16,700
Pension Contributions Above Required Minimum, Total				17,400
Pension Contributions			$ 6,700

X

- Definition

Pursuant to the terms of the settlement agreement with the Pension Benefit Guaranty Corporation, we will make additional contributions (above any minimum required contributions) to our defined benefit pension plans.

+ References

No definition available.

+ Details

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- Definition

The increase in the fair value of plan assets from contributions made by the employer.

+ 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 (b)(3)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

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- Definition

The amount of cash or cash equivalents contributed by the entity to fund its pension plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 25

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3536-108585

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