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Financial Guarantee Insurance Contracts - Summary of Gross Premium Receivable Roll-Forward (Direct and Assumed Contracts) (Detail) $ in Thousands, € in Millions, £ in Millions | 12 Months Ended |  |
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Dec. 31, 2021 USD ($) | Dec. 31, 2021 GBP (£) | Dec. 31, 2021 EUR (€) | Dec. 31, 2020 USD ($) | Dec. 31, 2020 GBP (£) | Dec. 31, 2020 EUR (€) | Dec. 31, 2019 USD ($) | Jan. 01, 2020 USD ($) | Dec. 31, 2018 USD ($)
Insurance [Line Items] |  |  |  |  |  |  |  |  |
Premium Receivable, Allowance for Credit Loss | $ 9,000 |  |  | $ 17,000 |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Beginning premium receivable | 370,000 |  |  | 416,000 |  |  | $ 495,000 |  |
Premium receipts | 35,000 |  |  | 46,000 |  |  | (48,000) |  |
Adjustments for changes in expected and contractual cash flows | (27,000) |  |  | (6,000) |  |  | (38,000) |  |
Accretion of premium receivable discount | 8,000 |  |  | 9,000 |  |  | 11,000 |  |
Financial Guarantee Insurance Contracts, Premium Receivable, Deconsolidation of VIE | 0 |  |  | 0 |  |  | 3,000 |  |
Uncollectable premiums | 8,000 |  |  | (4,000) |  |  | (2,000) |  |
Other adjustments (including foreign exchange) | (4,000) |  |  | 5,000 |  |  | (6,000) |  |
Ending premium receivable | 320,000 |  |  | 370,000 |  |  | 416,000 |  |
Allowance for Doubtful Accounts, Premiums and Other Receivables | 9,000 |  |  | 17,000 |  |  | 9,000 |  |
Premium Receivable, Credit Loss Expense (Reversal) | (6,000) |  |  | 9,000 |  |  |  |  |
Premium Receivable, Allowance for Credit Loss, Writeoff | (2,000) |  |  | (2,000) |  |  |  |  |
Premiums Receivable, Gross | 329,000 |  |  | 387,000 |  |  |  |  |
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest | 1,098,000 |  |  | 1,140,000 |  |  | 1,536,000 |  | $ 1,633,000
Everspan Group |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 2,000 |  |  |  |  |  |  |  |
Surveillance Category One [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 277,000 |  |  | 302,000 |  |  |  |  |
IA [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 12,000 |  |  | 40,000 |  |  |  |  |
II [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 6,000 |  |  | 3,000 |  |  |  |  |
III [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 22,000 |  |  | 27,000 |  |  |  |  |
IV [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 12,000 |  |  | 15,000 |  |  |  |  |
Premiums Receivable [Member] | Accounting Standards Update 2016-13 [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest |  |  |  |  |  |  |  | $ (3,000) |
United Kingdom, Pounds |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Beginning premium receivable | 117,000 | £ 86 |  | 129,000 | £ 97 |  |  |  |
Ending premium receivable | 108,000 | £ 80 |  | 117,000 | £ 86 |  | 129,000 |  |
Euro Member Countries, Euro |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Beginning premium receivable | 19,000 |  | € 16 | 26,000 |  | € 23 |  |  |
Ending premium receivable | 16,000 |  | € 14 | 19,000 |  | € 16 | $ 26,000 |  |
Structured Finance [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 45,000 |  |  | 59,000 |  |  |  |  |
Structured Finance [Member] | Mortgage-backed and Home Equity [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 16,000 |  |  | 22,000 |  |  |  |  |
Structured Finance [Member] | Student Loan [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 12,000 |  |  | 16,000 |  |  |  |  |
Structured Finance [Member] | Structured Insurance [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 10,000 |  |  | 14,000 |  |  |  |  |
Structured Finance [Member] | Other Structured Finance [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 7,000 |  |  | 7,000 |  |  |  |  |
Structured Finance [Member] | Surveillance Category One [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 19,000 |  |  | 27,000 |  |  |  |  |
Structured Finance [Member] | Surveillance Category One [Member] | Mortgage-backed and Home Equity [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 1,000 |  |  | 3,000 |  |  |  |  |
Structured Finance [Member] | Surveillance Category One [Member] | Student Loan [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 1,000 |  |  | 3,000 |  |  |  |  |
Structured Finance [Member] | Surveillance Category One [Member] | Structured Insurance [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 10,000 |  |  | 14,000 |  |  |  |  |
Structured Finance [Member] | Surveillance Category One [Member] | Other Structured Finance [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 7,000 |  |  | 7,000 |  |  |  |  |
Structured Finance [Member] | IA [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 1,000 |  |  | 0 |  |  |  |  |
Structured Finance [Member] | IA [Member] | Mortgage-backed and Home Equity [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 0 |  |  | 0 |  |  |  |  |
Structured Finance [Member] | IA [Member] | Student Loan [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 1,000 |  |  | 0 |  |  |  |  |
Structured Finance [Member] | IA [Member] | Structured Insurance [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 0 |  |  | 0 |  |  |  |  |
Structured Finance [Member] | IA [Member] | Other Structured Finance [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 0 |  |  | 0 |  |  |  |  |
Structured Finance [Member] | II [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 1,000 |  |  | 3,000 |  |  |  |  |
Structured Finance [Member] | II [Member] | Mortgage-backed and Home Equity [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 1,000 |  |  | 1,000 |  |  |  |  |
Structured Finance [Member] | II [Member] | Student Loan [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 0 |  |  | 2,000 |  |  |  |  |
Structured Finance [Member] | II [Member] | Structured Insurance [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 0 |  |  | 0 |  |  |  |  |
Structured Finance [Member] | II [Member] | Other Structured Finance [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 0 |  |  | 0 |  |  |  |  |
Structured Finance [Member] | III [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 12,000 |  |  | 14,000 |  |  |  |  |
Structured Finance [Member] | III [Member] | Mortgage-backed and Home Equity [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 2,000 |  |  | 3,000 |  |  |  |  |
Structured Finance [Member] | III [Member] | Student Loan [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 9,000 |  |  | 11,000 |  |  |  |  |
Structured Finance [Member] | III [Member] | Structured Insurance [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 0 |  |  | 0 |  |  |  |  |
Structured Finance [Member] | III [Member] | Other Structured Finance [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 0 |  |  | 0 |  |  |  |  |
Structured Finance [Member] | IV [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 12,000 |  |  | 15,000 |  |  |  |  |
Structured Finance [Member] | IV [Member] | Mortgage-backed and Home Equity [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 12,000 |  |  | 15,000 |  |  |  |  |
Structured Finance [Member] | IV [Member] | Student Loan [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 0 |  |  | 0 |  |  |  |  |
Structured Finance [Member] | IV [Member] | Structured Insurance [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 0 |  |  | 0 |  |  |  |  |
Structured Finance [Member] | IV [Member] | Other Structured Finance [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 0 |  |  | 0 |  |  |  |  |
Public Finance [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 159,000 |  |  | 185,000 |  |  |  |  |
Public Finance [Member] | Housing Revenue [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 157,000 |  |  | 168,000 |  |  |  |  |
Public Finance [Member] | Other Public Finance Sectors [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 2,000 |  |  | 17,000 |  |  |  |  |
Public Finance [Member] | Surveillance Category One [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 151,000 |  |  | 157,000 |  |  |  |  |
Public Finance [Member] | Surveillance Category One [Member] | Housing Revenue [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 149,000 |  |  | 155,000 |  |  |  |  |
Public Finance [Member] | Surveillance Category One [Member] | Other Public Finance Sectors [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 2,000 |  |  | 2,000 |  |  |  |  |
Public Finance [Member] | IA [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 3,000 |  |  | 27,000 |  |  |  |  |
Public Finance [Member] | IA [Member] | Housing Revenue [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 3,000 |  |  | 13,000 |  |  |  |  |
Public Finance [Member] | IA [Member] | Other Public Finance Sectors [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 0 |  |  | 15,000 |  |  |  |  |
Public Finance [Member] | II [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 5,000 |  |  | 0 |  |  |  |  |
Public Finance [Member] | II [Member] | Housing Revenue [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 5,000 |  |  | 0 |  |  |  |  |
Public Finance [Member] | II [Member] | Other Public Finance Sectors [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 0 |  |  | 0 |  |  |  |  |
Public Finance [Member] | III [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 0 |  |  | 0 |  |  |  |  |
Public Finance [Member] | III [Member] | Housing Revenue [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 0 |  |  | 0 |  |  |  |  |
Public Finance [Member] | III [Member] | Other Public Finance Sectors [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 0 |  |  | 0 |  |  |  |  |
Public Finance [Member] | IV [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 0 |  |  | 0 |  |  |  |  |
Public Finance [Member] | IV [Member] | Housing Revenue [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 0 |  |  | 0 |  |  |  |  |
Public Finance [Member] | IV [Member] | Other Public Finance Sectors [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 0 |  |  | 0 |  |  |  |  |
International Finance [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 125,000 |  |  | 144,000 |  |  |  |  |
International Finance [Member] | Sovereign/Sub-sovereign [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 93,000 |  |  | 108,000 |  |  |  |  |
International Finance [Member] | Investor-owned and Public Utilities [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 28,000 |  |  | 31,000 |  |  |  |  |
International Finance [Member] | Other International [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 5,000 |  |  | 5,000 |  |  |  |  |
International Finance [Member] | Surveillance Category One [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 107,000 |  |  | 118,000 |  |  |  |  |
International Finance [Member] | Surveillance Category One [Member] | Sovereign/Sub-sovereign [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 74,000 |  |  | 82,000 |  |  |  |  |
International Finance [Member] | Surveillance Category One [Member] | Investor-owned and Public Utilities [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 28,000 |  |  | 31,000 |  |  |  |  |
International Finance [Member] | Surveillance Category One [Member] | Other International [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 5,000 |  |  | 5,000 |  |  |  |  |
International Finance [Member] | IA [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 8,000 |  |  | 13,000 |  |  |  |  |
International Finance [Member] | IA [Member] | Sovereign/Sub-sovereign [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 8,000 |  |  | 13,000 |  |  |  |  |
International Finance [Member] | IA [Member] | Investor-owned and Public Utilities [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 0 |  |  | 0 |  |  |  |  |
International Finance [Member] | IA [Member] | Other International [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 0 |  |  | 0 |  |  |  |  |
International Finance [Member] | II [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 0 |  |  | 0 |  |  |  |  |
International Finance [Member] | II [Member] | Sovereign/Sub-sovereign [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 0 |  |  | 0 |  |  |  |  |
International Finance [Member] | II [Member] | Investor-owned and Public Utilities [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 0 |  |  | 0 |  |  |  |  |
International Finance [Member] | II [Member] | Other International [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 0 |  |  | 0 |  |  |  |  |
International Finance [Member] | III [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 11,000 |  |  | 13,000 |  |  |  |  |
International Finance [Member] | III [Member] | Sovereign/Sub-sovereign [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 11,000 |  |  | 13,000 |  |  |  |  |
International Finance [Member] | III [Member] | Investor-owned and Public Utilities [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 0 |  |  | 0 |  |  |  |  |
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Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | 0 |  |  | 0 |  |  |  |  |
International Finance [Member] | IV [Member] |  |  |  |  |  |  |  |  |
Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
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Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
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Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
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Financial Guarantee Insurance Contracts, Premium Receivable [Roll Forward] |  |  |  |  |  |  |  |  |
Premiums Receivable, Gross | $ 0 |  |  | $ 0 |  |  |  |  |

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