Retirement, Other Postretirement Benefits, and Defined Contribution Plans (Details 5) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011
Estimated Future Medicare Subsidy Receipts
2012	$ 5,678
2013	6,374
2014	7,137
2015	7,935
2016	8,828
2017 - 2021	59,306
Qualified Pension [Member]
Estimated Future Benefit Payments
2012	178,030
2013	189,881
2014	204,573
2015	220,295
2016	238,242
2017 - 2021	1,524,241
Non Qualified Pension [Member]
Estimated Future Benefit Payments
2012	11,199
2013	18,159
2014	14,942
2015	15,502
2016	22,492
2017 - 2021	72,724
Other Postretirement Trusts [Member]
Estimated Future Benefit Payments
2012	72,685
2013	76,731
2014	81,001
2015	85,780
2016	90,143
2017 - 2021	$ 523,040

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The amount of the aggregate benefits expected to be paid in the five fiscal years thereafter (the aggregate amount of benefits expected to be paid in years 6 through 10 after the date of the latest statement of financial position).

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

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-Name Accounting Standards Codification

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-Section 50

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The amount of the benefits expected to be paid in Year 5.

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The amount of the benefits expected to be paid in Year 4.

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The amount of the benefits expected to be paid in Year 1.

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The amount of the benefits expected to be paid in Year 3.

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The amount of the benefits expected to be paid in Year 2.

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Aggregate amount for the next five fiscal years following the first five fiscal years (that is the aggregate of fiscal years six through ten) following the balance sheet date of the prescription drug subsidy receipts expected to be received.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 60

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6414203&loc=d3e39716-114964

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Amount of the prescription drug subsidy receipts expected to be received in Year 5 after the balance sheet date.

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Amount of the prescription drug subsidy receipts expected to be received in Year 4 after the balance sheet date.

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Amount of the prescription drug subsidy receipts expected to be received in Year 3 after the balance sheet date.

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Amount of the prescription drug subsidy receipts expected to be received in Year 2 after the balance sheet date.

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