Employee Benefit Plans (Details 6) (USD $) In Millions	Dec. 31, 2010
Expected benefit payments and federal prescription drug subsidy
2011, Federal Prescription Drug Subsidy	$ (2)
2012, Federal Prescription Drug Subsidy	(3)
2013, Federal Prescription Drug Subsidy	(3)
2014, Federal Prescription Drug Subsidy	(3)
2015, Federal Prescription Drug Subsidy	(3)
2016-2020, Federal Prescription Drug Subsidy	(20)
Pension Benefits [Member]
Expected benefit payments and federal prescription drug subsidy
2011	51
2012	51
2013	54
2014	68
2015	75
2016-2020	536
Other Postretirement Benefits [Member]
Expected benefit payments and federal prescription drug subsidy
2011	18
2012	18
2013	18
2014	18
2015	19
2016-2020	$ 107

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).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
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The amount of the benefits expected to be paid in Year 5.

+ References

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

+ References

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

+ References

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- Definition

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

+ References

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-Number 132R
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The amount of the benefits expected to be paid in Year 2.

+ References

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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 FASB Staff Position (FSP)
-Number FAS106-2
-Paragraph 22

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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 1 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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