Insurance [Line Items]

No definition available.

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- Definition

Past Due Premiums Receivable

+ References

No definition available.

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- Definition

The valuation allowance as of the balance sheet date to reduce the gross amount of receivables to estimated net realizable value, which would be presented in parentheses on the face of the balance sheet.

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- Definition

Amount of the premium receivable for financial guarantee insurance contracts reported in the statement of financial position. This element primarily would consist of those financial guarantee insurance contracts which premiums are to be collected over the contract period, but may, on occasion, include premiums which are to be collected in full at inception, but which straddle a financial reporting period.

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- Definition

Amount of cash inflow from premiums received for premium receivable on financial guarantee insurance contracts.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of accretion of the discount for premiums receivable on financial guarantee insurance contracts.

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- Definition

Amount of increase (decrease) in the premium receivable on financial guarantee insurance contracts from changes in the period of the contract.

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- Definition

Amount of increase (decrease) in the premiums receivable on financial guarantee insurance contracts from adjustments classified as other.

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- Definition

Amortized cost of financing receivable 90 days or more past due and still accruing. Excludes net investment in lease.

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- Definition

Amount of investments classified as other.

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- Definition

Amount of expense (reversal of expense) for expected credit loss on premium receivable.

+ References

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- Definition

The carrying value as of the balance sheet date of the estimated valuation allowance to reduce gross premiums receivable to net realizable value.

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- Definition

Amount of increase (decrease) in allowance for credit loss on premium receivable.

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Amount of increase in allowance for credit loss on premium receivable from recovery.

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- Definition

Amount of writeoff of premium receivable, charged against allowance for credit loss.

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- Definition

The carrying amount as of the balance sheet date due the entity from (a) agents and insureds, (b) uncollected premiums and (c) others, net of the allowance for doubtful accounts.

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- Definition

Gross amount, as of the balance sheet date, due the entity from (a) agents and insureds, (b) uncollected premiums and (c) others, before deducting the allowance for doubtful accounts.

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- Definition

Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

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Financial Guarantee Insurance Contracts - Summary of Gross Premium Receivable Roll-Forward (Direct and Assumed Contracts) (Details) $ in Thousands, € in Millions, £ in Millions	3 Months Ended						9 Months Ended
	Sep. 30, 2023 USD ($)	Sep. 30, 2023 GBP (£)	Sep. 30, 2023 EUR (€)	Sep. 30, 2022 USD ($)	Sep. 30, 2022 GBP (£)	Sep. 30, 2022 EUR (€)	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Jun. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)	Jun. 30, 2022 USD ($)	Dec. 31, 2021 USD ($)
Insurance [Line Items]
Allowance for Doubtful Accounts, Premiums and Other Receivables	$ 4,000			$ 6,000			$ 4,000	$ 6,000	$ 5,000	$ 5,000	$ 6,000	$ 9,000
Past Due Premiums Receivable	0						0			0
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Beginning premium receivable							254,000	320,000
Premium receipts							22,000	30,000
Adjustments for changes in expected and contractual cash flows							6,000	(21,000)
Accretion of premium receivable discount							6,000	6,000
Uncollectable premiums							1,000	3,000
Other adjustments (including foreign exchange)							1,000	(20,000)
Ending premium receivable	245,000			259,000			245,000	259,000
Premium Receivable, Allowance for Credit Loss	4,000						4,000			5,000
Premium Receivable, Credit Loss Expense (Reversal)	0			(1,000)			(1,000)	(3,000)
Premium Receivable, Allowance for Credit Loss, Writeoff	0			0			0	0
Premium Receivable, Allowance for Credit Loss, Recovery	0			0			0	0
Financing Receivable, 90 Days or More Past Due, Still Accruing	0						0			0
Premiums Receivable, Gross	249,000						249,000			259,000
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	1,318,000			1,071,000			1,318,000	1,071,000	$ 1,303,000	1,305,000	$ 846,000	$ 1,098,000
Premiums Receivable, Net	278,000						278,000			269,000
Real Estate [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Other investments										22,000
Real Estate [Member] \| Foreign Exchange
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Other adjustments (including foreign exchange)							1,000	(19,000)
Specialty Property & Casualty Program
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	33,000						33,000			16,000
Public Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	143,000						143,000			150,000
Structured Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	22,000						22,000			24,000
International Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	84,000						84,000			85,000
I/SL [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	209,000						209,000			217,000
I/SL [Member] \| Public Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	136,000						136,000			142,000
I/SL [Member] \| Structured Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	4,000						4,000			5,000
I/SL [Member] \| International Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	70,000						70,000			70,000
IA [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	18,000						18,000			10,000
IA [Member] \| Public Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	3,000						3,000			3,000
IA [Member] \| Structured Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	0						0			1,000
IA [Member] \| International Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	14,000						14,000			7,000
II [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	5,000						5,000			5,000
II [Member] \| Public Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	5,000						5,000			5,000
II [Member] \| Structured Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	0						0			0
II [Member] \| International Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	0						0			0
III [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	7,000						7,000			16,000
III [Member] \| Public Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	0						0			0
III [Member] \| Structured Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	7,000						7,000			7,000
III [Member] \| International Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	0						0			9,000
IV [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	10,000						10,000			11,000
IV [Member] \| Public Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	0						0			0
IV [Member] \| Structured Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	10,000						10,000			11,000
IV [Member] \| International Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	0						0			0
United Kingdom, Pounds
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Ending premium receivable	71,000	£ 58		73,000	£ 66		71,000	73,000
Euro Member Countries, Euro
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Ending premium receivable	13,000		€ 13	$ 14,000		€ 14	13,000	$ 14,000
Other Public Finance Sectors [Member] \| Public Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	1,000						1,000			2,000
Other Public Finance Sectors [Member] \| I/SL [Member] \| Public Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	1,000						1,000			2,000
Other Public Finance Sectors [Member] \| IA [Member] \| Public Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	0						0			0
Other Public Finance Sectors [Member] \| II [Member] \| Public Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	0						0			0
Other Public Finance Sectors [Member] \| III [Member] \| Public Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	0						0			0
Other Public Finance Sectors [Member] \| IV [Member] \| Public Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	0						0			0
Other International [Member] \| International Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	3,000						3,000			2,000
Other International [Member] \| I/SL [Member] \| International Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	3,000						3,000			2,000
Other International [Member] \| IA [Member] \| International Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	0						0			0
Other International [Member] \| II [Member] \| International Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	0						0			0
Other International [Member] \| III [Member] \| International Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	0						0			0
Other International [Member] \| IV [Member] \| International Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	0						0			0
Mortgage Backed And Home Equity [Member] \| Structured Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	11,000						11,000			11,000
Mortgage Backed And Home Equity [Member] \| I/SL [Member] \| Structured Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	0						0			0
Mortgage Backed And Home Equity [Member] \| IA [Member] \| Structured Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	0						0			0
Mortgage Backed And Home Equity [Member] \| II [Member] \| Structured Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	0						0			0
Mortgage Backed And Home Equity [Member] \| III [Member] \| Structured Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	0						0			0
Mortgage Backed And Home Equity [Member] \| IV [Member] \| Structured Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	10,000						10,000			11,000
Student Loans [Member] \| Structured Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	8,000						8,000			8,000
Student Loans [Member] \| I/SL [Member] \| Structured Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	0						0			1,000
Student Loans [Member] \| IA [Member] \| Structured Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	0						0			1,000
Student Loans [Member] \| II [Member] \| Structured Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	0						0			0
Student Loans [Member] \| III [Member] \| Structured Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	7,000						7,000			7,000
Student Loans [Member] \| IV [Member] \| Structured Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	0						0			0
Other Structured Finance [Member] \| Structured Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	4,000						4,000			4,000
Other Structured Finance [Member] \| I/SL [Member] \| Structured Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	4,000						4,000			4,000
Other Structured Finance [Member] \| IA [Member] \| Structured Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	0						0			0
Other Structured Finance [Member] \| II [Member] \| Structured Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	0						0			0
Other Structured Finance [Member] \| III [Member] \| Structured Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	0						0			0
Other Structured Finance [Member] \| IV [Member] \| Structured Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	0						0			0
Sovereign And Sub Sovereign [Member] \| International Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	64,000						64,000			64,000
Sovereign And Sub Sovereign [Member] \| I/SL [Member] \| International Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	50,000						50,000			49,000
Sovereign And Sub Sovereign [Member] \| IA [Member] \| International Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	14,000						14,000			7,000
Sovereign And Sub Sovereign [Member] \| II [Member] \| International Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	0						0			0
Sovereign And Sub Sovereign [Member] \| III [Member] \| International Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	0						0			9,000
Sovereign And Sub Sovereign [Member] \| IV [Member] \| International Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	0						0			0
Investor Owned And Public Utilities [Member] \| International Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	17,000						17,000			18,000
Investor Owned And Public Utilities [Member] \| I/SL [Member] \| International Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	17,000						17,000			18,000
Investor Owned And Public Utilities [Member] \| IA [Member] \| International Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	0						0			0
Investor Owned And Public Utilities [Member] \| II [Member] \| International Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	0						0			0
Investor Owned And Public Utilities [Member] \| III [Member] \| International Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	0						0			0
Investor Owned And Public Utilities [Member] \| IV [Member] \| International Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	0						0			0
Housing Revenue [Member] \| Public Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	142,000						142,000			148,000
Housing Revenue [Member] \| I/SL [Member] \| Public Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	134,000						134,000			140,000
Housing Revenue [Member] \| IA [Member] \| Public Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	3,000						3,000			3,000
Housing Revenue [Member] \| II [Member] \| Public Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	5,000						5,000			5,000
Housing Revenue [Member] \| III [Member] \| Public Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	0						0			0
Housing Revenue [Member] \| IV [Member] \| Public Finance [Member]
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward]
Premiums Receivable, Gross	$ 0						$ 0			$ 0