Represents the number of transactions for which an action was brought in the state supreme court.

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- Definition

Represents the number of transactions for which lawsuits were filed by the entity alleging breaches of representations and warranties.

+ Details

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- Definition

Represents the number of transactions for which lawsuits were filed by the entity alleging violations of state securities laws and breach of contract, among other claims.

+ Details

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- Definition

Represents the outstanding principal amounts of the underlying insured obligations for financial guaranty contracts accounted for as insurance, net of ceded contracts.

+ Details

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- Definition

Represents the outstanding principal amounts of the underlying insured obligations for financial guaranty contracts accounted for as insurance.

+ Details

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- Definition

Represents the net outstanding principal amounts of the underlying insured obligations for financial guaranty contracts accounted for as insurance.

+ Details

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- Definition

Represents the percentage of reduction on the principal amounts of the underlying insured obligations for financial guaranty contracts accounted for as insurance.

+ Details

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- Definition

Represents the stated percentage on the principal amounts of the underlying insured obligations for financial guaranty contracts accounted for as insurance.

+ Details

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- Definition

Represents the amount of the transactions insured under financial guaranty insurance contracts.

+ Details

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- Definition

Represents the amount of the transactions insured under financial guaranty insurance contracts related to conversion of CDS form to financial guaranty form.

+ Details

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- Definition

Represents the change in the entity's estimate of the present value of future claim payments, net of reinsurance and net of salvage and subrogation which includes the present value benefit of estimated recoveries for breaches of R&W, including the effect of consolidating VIEs.

+ Details

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- Definition

Total amount of cumulative payments made to date to settle insured claims and pay costs incurred in the claims settlement process.

+ Details

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- Definition

Liability as of the balance sheet date for amounts representing estimated cost of settling unpaid claims under the terms of the underlying insurance policies, less estimated reinsurance recoveries on such claims, for the largest loss on a single insured transaction.

+ Details

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- Definition

Represents the number of transactions for which estimated loss was projected.

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- Definition

Alternate concept name for the aggregate amount of policy reserves (provided for future obligations including unpaid claims and claims adjustment expenses) and policy benefits (liability for future policy benefits) as of the balance sheet date, net of reinsurance recoverable on unpaid losses.

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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.

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Financial Guaranty Insurance Contracts (Details 9) In Millions, unless otherwise specified			9 Months Ended																9 Months Ended						9 Months Ended
	Sep. 30, 2011 USD ($) security segment entity agreement market subsidiary company policy D transaction counterparty	Dec. 31, 2010 USD ($)	Sep. 30, 2011 "XXX" Life Insurance Transactions USD ($)	Sep. 30, 2011 "XXX" Life Insurance Transactions Below investment grade ("BIG") USD ($)	Sep. 30, 2011 Public finance Below investment grade ("BIG") USD ($)	Sep. 30, 2011 Student Loan USD ($)	Sep. 30, 2011 Student loan. USD ($)	Sep. 30, 2011 Student loan. Below investment grade ("BIG") USD ($)	Sep. 30, 2011 Asset-backed student loan USD ($)	Sep. 30, 2011 Asset-backed student loan Below investment grade ("BIG") USD ($)	Sep. 30, 2011 Jefferson County Alabama Sewer Authority USD ($)	Sep. 30, 2011 Jefferson County Alabama Sewer Authority Warrants USD ($)	Sep. 30, 2011 Jefferson County Alabama Sewer Authority Warrants AGM USD ($)	Sep. 30, 2011 Jefferson County Alabama Sewer Authority Warrants AG Re and AGC USD ($)	Sep. 30, 2011 Jefferson County Alabama Sewer Authority Bonds USD ($)	Sep. 30, 2011 Jefferson County Alabama Sewer Authority Bonds AGM USD ($)	Sep. 30, 2011 Jefferson County Alabama Sewer Authority Bonds AG Re and AGC USD ($)	Sep. 30, 2011 Telephone directory "yellow pages" USD ($)	Sep. 30, 2011 Manufactured housing loans USD ($) transaction	Sep. 30, 2011 Manufactured housing loans Below investment grade ("BIG") USD ($)	Sep. 30, 2011 Harrisburg, Pennsylvania USD ($)	Sep. 30, 2011 Harrisburg, Pennsylvania Below investment grade ("BIG") USD ($)	Sep. 30, 2011 Trust Preferred Securities Collateralized Debt Obligations Member USD ($)	Sep. 30, 2011 Trust Preferred Securities Collateralized Debt Obligations Member Below investment grade ("BIG") USD ($)	Sep. 30, 2011 Sovereign debt of Greece with a 4.5% fixed coupon EUR (€)	Sep. 30, 2011 Sovereign debt of Greece due in 2057 with a 2.085% inflation-linked coupon EUR (€)
Financial guarantee obligations
Net Par Outstanding Financial Guaranty Insurance			$ 2,000.0	$ 882.5	$ 240.0	$ 2,800.0	$ 1,300.0		$ 1,500.0	$ 678.7	$ 731.8	$ 495.8	$ 135.2	$ 360.6	$ 236.0	$ 164.1	$ 71.9	$ 110.7	$ 347.7	$ 233.6	$ 170.1	$ 97.5	$ 1,900.0	$ 812.7
Amount of transactions insured converted from CDS form to financial guaranty form																							837.8
Increase in projected expected loss to be paid primarily to a reduction in the discount rate used discount projected losses			61.3																1.1
Largest expected loss to be paid for a single transaction			133.2			32.5		25.9		60.4		18.0			1.0			17.6	15.6				13.1
Loss and LAE reserve, net	622.7	552.1
Number of transactions for which estimated loss was projected																			1
Amount of transactions insured																			65.1
Net claims to date																					5.1
Number of U.S. RMBS transactions for which lawsuits were filed alleging breaches of R&W	6
Number of U.S. RMBS transactions for which action was brought in the Supreme Court of the State of New York	6
Number of U.S. RMBS transactions for which lawsuits were filed alleging violations of state securities laws and other claims	2
Exposure of debt																									200.0	113.5
Net Exposure of debt																									€ 165.1	€ 52.4
Coupon rate (as a percent)																									4.50%	2.085%
Reduction of the notional amount due to relief measures related to sovereign debt of Greece (as a percent)																									50.00%