Fair Value Of Financial Instruments (Aggregate Fair Value And The Aggregate Remaining Contractual Principal Balance Outstanding) (Details) (USD $) In Millions	Sep. 30, 2011	Dec. 31, 2010
Schedule of Fair Value of Separate Accounts by Major Category of Investment [Line Items]
Loans, Contractual Outstanding Principal	$ 3,533	$ 4,138
Loans, Fair Value	2,218	2,183
Loans, Difference	1,315	1,955
Long-term debt, Contractual Outstanding Principal	17,361	17,217
Long-term debt, Aggregate fair value	5,123	6,680
Long-term debt, Difference	12,238	10,537
Other Loans [Member]
Schedule of Fair Value of Separate Accounts by Major Category of Investment [Line Items]
Loans, 90 days or more past due, Contractual Outstanding Principal	154	149
Loans, 90 days or more past due, Fair Value	47	45
Loans, 90 days or more past due, Difference	107	104
Loans, Contractual Outstanding Principal	299	412
Loans, Fair Value	92	124
Loans, Difference	207	288
Residential Mortgage Loans [Member]
Schedule of Fair Value of Separate Accounts by Major Category of Investment [Line Items]
Loans, 90 days or more past due, Contractual Outstanding Principal	238	243
Loans, 90 days or more past due, Fair Value
Loans, 90 days or more past due, Difference	238	243
Loans, Contractual Outstanding Principal	2,842	3,334
Loans, Fair Value	2,079	2,014
Loans, Difference	$ 763	$ 1,320

Fair Value Option Aggregate Fair Value Loans Ninety Days Or More Past Due

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Fair Value Option Aggregate Fair Value Loans Receivable

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Fair Value Option Aggregate Fair Value Long Term Debt Instruments

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Fair Value Option Contractual Outstanding Principal Loans Receivable

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Fair Value Option Contractual Outstanding Principal Long Term Debt Instruments

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- Definition

This item represents the difference between the aggregate fair value and the aggregate unpaid principal balance of loans and long-term receivables (other than securities categorized as trading, available-for-sale or held-to-maturity) that have contractual principal amounts and for which the fair value option has been elected.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 159

-Paragraph 18

-Subparagraph d(1)

-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.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

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-Section 50

-Paragraph 28

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This item represents the difference between the aggregate fair value and the aggregate unpaid principal balance of long-term debt instruments that have contractual principal amounts and for which the fair value option has been elected.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 159

-Paragraph 18

-Subparagraph d(2)

-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.

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-Publisher FASB

-Name Accounting Standards Codification

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This item represents the aggregate fair value of loans held as assets that are 90 days or more past due for which the fair value option has been elected.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 159

-Paragraph 18

-Subparagraph e(1)

-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 825

-SubTopic 10

-Section 50

-Paragraph 28

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For loans held as assets for which the fair value option has been elected, this item represents the difference between the aggregate fair value and the aggregate unpaid principal balance of those loans that are 90 days or more past due.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

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This item represents the aggregate fair value of loans held as assets that are in nonaccrual status for which the fair value option has been elected, if the entity's policy is to recognize interest income separately from other changes in fair value.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 159

-Paragraph 18

-Subparagraph e(2)

-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 825

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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