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Fair Value Of Financial Instruments (Gains And Losses On Fair Value Option Included In The Company's Consolidated Statements Of Operations) (Detail) (USD $) In Millions, unless otherwise specified | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012
Accounts Notes And Loans Receivable [Line Items] |  |  |  |
Net gains (losses) on financial instruments at fair value and foreign exchange | $ 5 | $ 7 | $ 62 | $ (18)
Loan Repurchase Commitments [Member] |  |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |  |
Net gains (losses) on financial instruments at fair value and foreign exchange | 1 | 19 | 140 | 62
Fixed Maturity Securities Held At Fair Value [Member] |  |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |  |
Net gains (losses) on financial instruments at fair value and foreign exchange | (37) | 21 | (35) | (36)
Residential Mortgage Loans [Member] |  |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |  |
Net gains (losses) on financial instruments at fair value and foreign exchange | (87) | (4) | (16) | (103)
Other Loans [Member] |  |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |  |
Net gains (losses) on financial instruments at fair value and foreign exchange | 0 | (7) | 13 | (48)
Other Assets [Member] |  |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |  |
Net gains (losses) on financial instruments at fair value and foreign exchange | 0 | 0 | 0 | 0
Long Term Debt [Member] |  |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |  |
Net gains (losses) on financial instruments at fair value and foreign exchange | $ 164 | $ 12 | $ 85 | $ 140

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