Employee Benefit Plans Defined Benefit Plan - Expected Future Benefit Payments (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014
Qualified Pension
Defined Benefit Plan Disclosure [Line Items]
Expected employer contributions for 2013	$ 16,190
Expected Benefit Payments [Abstract]
2015	6,311
2016	7,165
2017	8,244
2018	10,447
2019	11,347
2020-2024	81,870
Post-retirement Healthcare
Defined Benefit Plan Disclosure [Line Items]
Expected employer contributions for 2013	6,021
Expected Benefit Payments [Abstract]
2015	6,021
2016	7,506
2017	9,199
2018	11,166
2019	13,439
2020-2024	109,814
Expected Subsidy [Abstract]
2015	12
2016	28
2017	48
2018	76
2019	114
2020-2024	$ 1,610

Defined Benefit Plan, Expected Future Benefit Subsidies, Five Fiscal Years Thereafter

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Defined Benefit Plan, Expected Future Benefit Subsidies, Next Fiscal Year

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Defined Benefit Plan, Expected Future Benefit Subsidies, Year Five

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Defined Benefit Plan, Expected Future Benefit Subsidies, Year Four

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- Definition

Amount of benefits from a defined benefit plan expected to be paid in the five fiscal years after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ 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 (f)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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Amount of benefits from a defined benefit plan expected to be paid in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of benefits from a defined benefit plan expected to be paid in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of benefits from a defined benefit plan expected to be paid in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of benefits from a defined benefit plan expected to be paid in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of benefits from a defined benefit plan expected to be paid in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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- Definition

Amount of employer's best estimate of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position.

+ 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 (g)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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