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Fair Value Of Financial Instruments (Changes In Fair Value Included In the Company's Consolidated Income Statement) (Details) (USD $) In Millions, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2011 | Dec. 31, 2010
Fixed Maturity Securities Held At Fair Value [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Net Gains (Losses) on Financial Instruments at Fair Value and Foreign Exchange | $ (484) | $ 374
Other Assets [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Net Gains (Losses) on Financial Instruments at Fair Value and Foreign Exchange |  | 26
Long-Term Debt [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Net Gains (Losses) on Financial Instruments at Fair Value and Foreign Exchange | 594 | (661)
Other Loans [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Net Gains (Losses) on Financial Instruments at Fair Value and Foreign Exchange | (19) | (26)
Residential Mortgage Loans [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Net Gains (Losses) on Financial Instruments at Fair Value and Foreign Exchange | (143) | 295
Loan Repurchase Commitments [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Net Gains (Losses) on Financial Instruments at Fair Value and Foreign Exchange | $ 242 | $ 336

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- Definition Change in the fair value of and realized gains and losses on financial instruments and foreign exchange included in earnings. + References No definition available. + Details
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- Details
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