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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 | 6 Months Ended
--- | --- | ---
Jun. 30, 2013 | Jun. 30, 2012 | Jun. 30, 2013 | Jun. 30, 2012
Accounts Notes And Loans Receivable [Line Items] |  |  |  |
Net gains (losses) on financial instruments at fair value and foreign exchange | $ (6) | $ (6) | $ 57 | $ (25)
Loan Repurchase Commitments [Member] |  |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |  |
Net gains (losses) on financial instruments at fair value and foreign exchange | 50 | 44 | 139 | 43
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 | (16) | (56) | 2 | (57)
Residential Mortgage Loans [Member] |  |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |  |
Net gains (losses) on financial instruments at fair value and foreign exchange | 145 | (117) | 71 | (99)
Other Loans [Member] |  |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |  |
Net gains (losses) on financial instruments at fair value and foreign exchange | 0 | (2) | 13 | (41)
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 | $ (160) | $ 135 | $ (79) | $ 128

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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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