Credit Derivative, Collateral Terminated

No definition available.

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- Definition

Credit Derivative, Gross Par Of Contracts Terminated

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Credit Derivative, Unrealized Gain (Loss) on Termination of Transactions, Fair Value

+ References

No definition available.

+ Details

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- Definition

Represents the outstanding principal amounts of the underlying insured obligations that are accounted for as credit derivatives, net of protection purchased.

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No definition available.

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- Definition

Gain (Loss) Due to Change in Methodology in Expected Recoveries

+ References

No definition available.

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

Number of Transactions Terminated

+ References

No definition available.

+ Details

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- Definition

Transaction Termination, Number of Counterparties

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No definition available.

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- Definition

Average period covered by credit risk derivative contracts, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4K
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5708775-113959

+ Details

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- Definition

The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624258-113959

+ Details

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Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Contracts Accounted for as Credit Derivatives - Narrative (Details) $ in Millions	12 Months Ended
	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($) Transaction Counterparty
Credit Derivatives
Estimated remaining weighted average life of credit derivatives (in years)	11 years 8 months	5 years 3 months 6 days
Net par outstanding	$ 6,207	$ 16,997
Fair value gains			$ 49
Collateral agreed to be posted	18	116
Market value collateralized debt obligations of corporate obligations [Member]
Credit Derivatives
Net par outstanding	878	10,425
Pooled infrastructure [Member]
Credit Derivatives
Net par outstanding	1,561	1,513
Commercial Mortgage Backed Securities (CMBS) [Member]
Credit Derivatives
Unrealized fair value gain on termination of transactions			41
Triple-X Life Insurance Transaction [Member]
Credit Derivatives
Unrealized fair value gain on termination of transactions			$ 99
Collateral Debt Obligations, Collateral Cap Negotiated [Member]
Credit Derivatives
Credit Derivative, Gross Par Of Contracts Terminated		183
Credit Derivative, Collateral Terminated		73
Alt-A [Member] \| First Lien [Member] \| Residential Mortgage-Backed Securities (RMBS) [Member]
Credit Derivatives
Counterparties involved in transaction termination \| Counterparty			1
Number of transactions terminated \| Transaction			5
Unrealized fair value gain on termination of transactions			$ 213
Collateralized Loan Obligations and Collateral Bond Obligations [Member] \| Market value collateralized debt obligations of corporate obligations [Member]
Credit Derivatives
Net par outstanding	$ 0	$ 2,022
Unrealized fair value gain on termination of transactions			$ 99