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Fair Value Of Financial Instruments (Aggregate Fair Value And The Aggregate Remaining Contractual Principal Balance Outstanding) (Details) (USD $) In Millions, unless otherwise specified | Dec. 31, 2011 | Dec. 31, 2010
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Schedule of Fair Value of Separate Accounts by Major Category of Investment [Line Items] |  |
Loans, Contractual Outstanding Principal | $ 3,481 | $ 4,138
Loans, Fair Value | 2,046 | 2,183
Loans, Difference | 1,435 | 1,955
Long-term debt, Contractual Outstanding Principal | 13,583 | 17,217
Long-term debt, Aggregate fair value | 4,754 | 6,680
Long-term debt, Difference | 8,829 | 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 | 324 | 149
Loans, 90 days or more past due, Fair Value | 108 | 45
Loans, 90 days or more past due, Difference | 216 | 104
Loans, Contractual Outstanding Principal | 129 | 412
Loans, Fair Value | 43 | 124
Loans, Difference | 86 | 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 | 259 | 243
Loans, 90 days or more past due, Difference | 259 | 243
Loans, Contractual Outstanding Principal | 2,769 | 3,334
Loans, Fair Value | 1,895 | 2,014
Loans, Difference | $ 874 | $ 1,320

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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of Financial Accounting Standard (FAS) -Number 159 -Paragraph 18 -Subparagraph d(1) -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 28 -Subparagraph (d)(1) -URI http://asc.fasb.org/extlink&oid=6957238&loc=d3e14064-108612 + Details
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- Definition 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. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 28 -Subparagraph (d)(2) -URI http://asc.fasb.org/extlink&oid=6957238&loc=d3e14064-108612 + Details
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- Definition 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 -Subparagraph (e)(1) -URI http://asc.fasb.org/extlink&oid=6957238&loc=d3e14064-108612 + Details
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