Employee Benefit Plans (Expected Benefit Payments) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014
Qualified Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
2015	$ 61,381
2016	65,705
2017	70,081
2018	74,579
2019	79,480
2020-2024	465,421
Non-Qualified Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
2015	5,148
2016	5,191
2017	5,257
2018	5,240
2019	5,234
2020-2024	25,705
Postretirement Medical Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
2015	4,389
2016	4,582
2017	4,980
2018	5,373
2019	5,626
2020-2024	$ 27,946

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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

+ Details

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- Definition

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.

+ References

+ Details

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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.

+ References

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- Definition

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.

+ References

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- Definition

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.

+ References

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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.

+ References

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