Leases (Future Minimum Capital Lease Payments) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011
Component of Operating Other Cost and Expense [Line Items]
2012	$ 15
2013	15
2014	15
2015	15
2016	15
Thereafter	128
Total	203
Less: amount representing interest	96
Present value of net minimum capital lease payments	107
Capital Lease Obligations [Member]
Component of Operating Other Cost and Expense [Line Items]
2012	1
2013	1
2014	1
Thereafter	1
Total	4
Less: amount representing interest	1
Present value of net minimum capital lease payments	$ 3

The total of contractually required rental payments on leases meeting the criteria for capitalization.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 16

-Subparagraph a(ii)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6455398&loc=d3e45280-112737

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Contractually required rental payments on leases meeting the criteria for capitalization, due within one year of the balance sheet date.

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Contractually required rental payments on leases meeting the criteria for capitalization, due within the fifth year from the balance sheet date.

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Contractually required rental payments on leases meeting the criteria for capitalization, due within the fourth year from the balance sheet date.

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Contractually required rental payments on leases meeting the criteria for capitalization, due within the third year from the balance sheet date.

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Contractually required rental payments on leases meeting the criteria for capitalization, due within the second year from the balance sheet date.

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Contractually required rental payments due on leases meeting the criteria for capitalization, after the fifth year from the balance sheet date.

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Amount necessary to reduce net minimum lease payments to present value calculated at the lesser of the interest rate implicit in the lease (if known) or the entity's incremental borrowing rate (as defined) at inception of the lease.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 10

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 16

-Subparagraph a(ii)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 7

-Subparagraph d

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (b)

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The discounted value of future cash flows under leases meeting the criteria for capitalization.

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