For financial guaranty insurance contracts, represents the number of insured transactions.

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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 amount of the transactions insured under financial guaranty insurance contracts.

+ 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.

+ Details

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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.

+ Details

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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.

+ Details

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Financial Guaranty Insurance Contracts (Details 9) (USD $) In Millions, unless otherwise specified																			6 Months Ended
	Jun. 30, 2011 Counterparties Securities Agreements Policies D Subsidiaries Markets Companies FiscalQuarters Entities Transactions	Dec. 31, 2010	Jun. 30, 2011 "XXX" Life Insurance Transactions	Jun. 30, 2011 "XXX" Life Insurance Transactions Below investment grade ("BIG") Transactions	Jun. 30, 2011 Student Loan	Jun. 30, 2011 Student loan.	Jun. 30, 2011 Student loan. Below investment grade ("BIG")	Jun. 30, 2011 Asset-backed student loan	Jun. 30, 2011 Asset-backed student loan Below investment grade ("BIG")	Jun. 30, 2011 Jefferson County Alabama Sewer Authority	Sep. 30, 2011 Jefferson County Alabama Sewer Authority Warrants	Jun. 30, 2011 Jefferson County Alabama Sewer Authority Warrants	Jun. 30, 2011 Jefferson County Alabama Sewer Authority Warrants AGM	Jun. 30, 2011 Jefferson County Alabama Sewer Authority Warrants AG Re and AGRO	Jun. 30, 2011 Jefferson County Alabama Sewer Authority Bonds	Jun. 30, 2011 Jefferson County Alabama Sewer Authority Bonds AGM	Jun. 30, 2011 Jefferson County Alabama Sewer Authority Bonds AG Re and AGRO	Jun. 30, 2011 Telephone directory "yellow pages"	Jun. 30, 2011 Manufactured housing loans Transactions	Jun. 30, 2011 Manufactured housing loans Below investment grade ("BIG")	Jun. 30, 2011 Harrisburg, Pennsylvania	Jun. 30, 2011 Harrisburg, Pennsylvania Below investment grade ("BIG")	Aug. 09, 2011 Second lien Transactions
Financial guarantee obligations
Net Par Outstanding Financial Guaranty Insurance			$ 2,000.0	$ 882.5	$ 2,900.0	$ 1,400.0	$ 531.9	$ 1,500.0	$ 242.3	$ 731.8		$ 495.8	$ 135.2	$ 360.6	$ 236.0	$ 164.1	$ 71.9	$ 110.7	$ 67.1	$ 240.5	$ 165.0	$ 93.1
Largest expected loss to be paid for a single transaction				72.9	32.8		12.6		60.7		18.0	31.1			1.0			6.5	14.5
Loss and LAE reserve, net	492.1	552.1	61.2
Number of insured transactions				2
Amount of transactions insured																			358.8
Net claims to date																					$ 4.5
Number of U.S. RMBS transactions for which lawsuits were filed alleging violations of state securities laws and other claims	2																						6
Number of transactions for which estimated loss was projected																			1