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Derivative Instruments (Credit Derivatives Sold) (Detail) (Insurance Operations [Member], USD $) In Millions, unless otherwise specified | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2014 | Dec. 31, 2013
Derivative [Line Items] |  |
Derivative notional amount | $ 15,387 | $ 28,935
Total fair value of credit derivatives | (288) | (1,152)
Credit Default Swap [Member] |  |
Derivative [Line Items] |  |
Weighted average remaining expected maturity | 1 year 10 months 24 days | 2 years 7 months 6 days
Derivative notional amount | 11,276 | 23,954
Total fair value of credit derivatives | (284) | (1,132)
Insured Swaps [Member] |  |
Derivative [Line Items] |  |
Weighted average remaining expected maturity | 16 years 4 months 24 days | 18 years 6 months 0 days
Derivative notional amount | 4,111 | 4,945
Total fair value of credit derivatives | (4) | (5)
Other Credit Derivatives [Member] |  |
Derivative [Line Items] |  |
Weighted average remaining expected maturity |  | 28 years 0 months 0 days
Derivative notional amount | 0 | 36
Total fair value of credit derivatives | 0 | (15)
Credit Rating Aaa [Member] |  |
Derivative [Line Items] |  |
Derivative notional amount | 6,926 | 7,406
Total fair value of credit derivatives | (2) | (2)
Credit Rating Aaa [Member] | Credit Default Swap [Member] |  |
Derivative [Line Items] |  |
Derivative notional amount | 6,926 | 7,406
Credit Rating Aaa [Member] | Insured Swaps [Member] |  |
Derivative [Line Items] |  |
Derivative notional amount | 0 | 0
Credit Rating Aaa [Member] | Other Credit Derivatives [Member] |  |
Derivative [Line Items] |  |
Derivative notional amount | 0 | 0
Credit Rating Aa [Member] |  |
Derivative [Line Items] |  |
Derivative notional amount | 584 | 2,049
Total fair value of credit derivatives | 0 | 0
Credit Rating Aa [Member] | Credit Default Swap [Member] |  |
Derivative [Line Items] |  |
Derivative notional amount | 435 | 1,972
Credit Rating Aa [Member] | Insured Swaps [Member] |  |
Derivative [Line Items] |  |
Derivative notional amount | 149 | 77
Credit Rating Aa [Member] | Other Credit Derivatives [Member] |  |
Derivative [Line Items] |  |
Derivative notional amount | 0 | 0
Credit Rating A [Member] |  |
Derivative [Line Items] |  |
Derivative notional amount | 3,933 | 4,350
Total fair value of credit derivatives | (2) | (3)
Credit Rating A [Member] | Credit Default Swap [Member] |  |
Derivative [Line Items] |  |
Derivative notional amount | 968 | 1,068
Credit Rating A [Member] | Insured Swaps [Member] |  |
Derivative [Line Items] |  |
Derivative notional amount | 2,965 | 3,282
Credit Rating A [Member] | Other Credit Derivatives [Member] |  |
Derivative [Line Items] |  |
Derivative notional amount | 0 | 0
Credit Rating Bbb [Member] |  |
Derivative [Line Items] |  |
Derivative notional amount | 1,177 | 9,138
Total fair value of credit derivatives | (2) | (78)
Credit Rating Bbb [Member] | Credit Default Swap [Member] |  |
Derivative [Line Items] |  |
Derivative notional amount | 201 | 7,552
Credit Rating Bbb [Member] | Insured Swaps [Member] |  |
Derivative [Line Items] |  |
Derivative notional amount | 976 | 1,586
Credit Rating Bbb [Member] | Other Credit Derivatives [Member] |  |
Derivative [Line Items] |  |
Derivative notional amount | 0 | 0
Credit Rating Below Investment Grade [Member] |  |
Derivative [Line Items] |  |
Derivative notional amount | 2,767 | 5,992
Total fair value of credit derivatives | (282) | (1,069)
Credit Rating Below Investment Grade [Member] | Credit Default Swap [Member] |  |
Derivative [Line Items] |  |
Derivative notional amount | 2,746 | 5,956
Credit Rating Below Investment Grade [Member] | Insured Swaps [Member] |  |
Derivative [Line Items] |  |
Derivative notional amount | 21 | 0
Credit Rating Below Investment Grade [Member] | Other Credit Derivatives [Member] |  |
Derivative [Line Items] |  |
Derivative notional amount | $ 0 | $ 36

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- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column B + Details
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- Definition Weighted Average Remaining Maturity Credit Derivatives In Years + References No definition available. + Details
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- Definition Fair value of credit risk derivative liability. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=28364263&loc=d3e13433-108611 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4K -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5708775-113959 + Details
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- Details
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