This element represents the gross amount of claim payments during the period

No definition available.

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- Definition

Amount of outstanding bonds for a specific issuer

+ References

No definition available.

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- Definition

Payment For Sale Of Subsidiary

+ References

No definition available.

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- 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.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
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- Definition

Date the entity disposed of a business or a group of assets, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Amount of gain (loss) on sale or disposal of equity in securities of subsidiaries.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Paragraph 1
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- Definition

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

+ References

No definition available.

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- Definition

The cash inflow from a borrowing with the highest claim on the assets of the entity in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle, if longer).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition

The cash inflow from a borrowing where a lender is placed in a lien position behind debt having a higher priority of repayment (senior) in liquidation of the entity's assets or underlying collateral.

+ References

+ Details

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- Definition

Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

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Business Developments And Risks And Uncertainties (Narrative) (Detail) $ in Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2017 USD ($) segments	Mar. 31, 2017 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)
Business Acquisition [Line Items]
Number of operating segments \| segments	3
Fixed-to-Floating rate Surplus Notes	14.00%			14.00%
Income (loss) before income taxes	$ (210)		$ (55)	$ (330)	$ (156)
Proceeds from Senior Lenders				325
Valuation allowance taken in current period	1,100	$ 55		1,200
Zohar II [Member]
Business Acquisition [Line Items]
Claims payments				770
Puerto Rico [Member]
Business Acquisition [Line Items]
Claims payments				242
Mbia Inc [Member]
Business Acquisition [Line Items]
Proceeds from subordinated financing				38
Mbia Corp [Member] \| Zohar II [Member]
Business Acquisition [Line Items]
Claims payments				60
Assured Guaranty Corp [Member]
Business Acquisition [Line Items]
Payment for sale of subsidiary				23
Assured Guaranty Corp [Member] \| Zohar II [Member]
Business Acquisition [Line Items]
Outstanding bonds	$ 347			347
MBIA UK [Member]
Business Acquisition [Line Items]
Gain recorded on adjustment of carrying value to fair value less costs to sell				$ 5
Income (loss) before income taxes			$ 12		$ 23
Sale effective date	Jan. 10, 2017