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Long-Term Debt (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020 | Feb. 12, 2018
Debt Instrument [Line Items] |  |  |  |
Tier 2 Note Security in RMBS Litigation Settlement Proceeds |  |  |  | $ 1,600
Long-term debt | $ 639 | $ 2,230 |  |
Debt Instrument, Interest Rate, Effective Percentage | 7.00% |  |  |
Net realized gains on extinguishment of debt | $ 81 | 33 | $ 0 |
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months | 665 |  |  |
Long-term Debt, Maturities, Repayments of Principal in Year Two | 0 |  |  |
Long-term Debt, Maturities, Repayments of Principal in Year Three | 0 |  |  |
Long-term Debt, Maturities, Repayments of Principal in Year Four | 0 |  |  |
Long-term Debt, Maturities, Repayments of Principal in Year Five | 0 |  |  |
Paydown of Ambac Note |  | 1,641 | $ 121 |
Long-term Debt, Maturities, Repayments of Principal after Year Five | $ 41 |  |  |
Tier 2 Notes [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 8.50% |  |  |
Debt Instrument, Interest Rate, Effective Percentage | 9.90% |  |  |
Debt Instrument, Face Amount | $ 146 |  |  |
Paid-in-Kind Interest | $ 49 | 93 |  |
Sitka AAC Note |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt Instrument, Interest Rate, Effective Percentage | 5.70% |  |  |
Ambac Assurance Corporation [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Long-term debt | $ 639 | 2,230 |  |
Long-term Debt, Gross | 706 | 2,334 |  |
Debt Instrument, Unamortized Discount (Premium), Net | (67) | (104) |  |
Ambac Assurance Corporation [Member] | Tier 2 Notes [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Long-term debt | 146 | 333 |  |
Long-term Debt, Gross | 146 | 333 |  |
Debt Instrument, Unamortized Discount (Premium), Net | 0 | 0 |  |
Ambac Assurance Corporation [Member] | 5.1% Surplus Notes, General Account, Due 2020 [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Long-term debt | 477 | 729 |  |
Long-term Debt, Gross | 519 | 785 |  |
Debt Instrument, Unamortized Discount (Premium), Net | (42) | (56) |  |
Net realized gains on extinguishment of debt | 33 |  |  |
Ambac Assurance Corporation [Member] | Sitka AAC Note |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Long-term debt | 0 | 1,154 |  |
Debt Instrument, Unamortized Discount (Premium), Net | 0 | (21) |  |
Debt Instrument, Face Amount | 0 | 1,175 |  |
Net realized gains on extinguishment of debt | $ 53 |  |  |
Ambac UK [Member] | Secured Debt [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 0.00% |  |  |
Long-term debt | $ 16 | 15 |  |
Long-term Debt, Gross | 41 | 41 |  |
Debt Instrument, Unamortized Discount (Premium), Net | $ (25) | $ (26) |  |
Debt Instrument, Interest Rate, Effective Percentage | 7.40% |  |  |
5.1 % Surplus Notes Due 2020 [Member] | Ambac Assurance Corporation [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 5.10% | 5.10% |  |
5.1% Surplus Notes, General Account, Due 2020 [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Net realized gains on extinguishment of debt | $ (134) |  |  |
Debt Instrument, Repurchased During Period | 266 |  |  |
Consolidated Variable Interest Entities [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Unpaid Principal Amount Of Fixed Rate Debt Accounted For Under Fair Value Option | 3,388 | $ 3,739 |  |
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months | 0 |  |  |
Long-term Debt, Maturities, Repayments of Principal in Year Two | 0 |  |  |
Long-term Debt, Maturities, Repayments of Principal in Year Three | 26 |  |  |
Long-term Debt, Maturities, Repayments of Principal in Year Four | 0 |  |  |
Long-term Debt, Maturities, Repayments of Principal in Year Five | 0 |  |  |
Long-term Debt, Maturities, Repayments of Principal after Year Five | $ 3,362 |  |  |
Consolidated Variable Interest Entities [Member] | Minimum [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt Instrument, Interest Rate, Effective Percentage | 0.00% | 0.00% |  |
Consolidated Variable Interest Entities [Member] | Maximum [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt Instrument, Interest Rate, Effective Percentage | 7.93% | 7.93% |  |
London Interbank Offered Rate (LIBOR) [Member] | Sitka AAC Note |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Long-term Debt, Percentage Bearing Variable Interest, Percentage Rate | 4.50% |  |  |
London Interbank Offered Rate (LIBOR) [Member] | Minimum [Member] | Sitka AAC Note |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Long-term Debt, Percentage Bearing Variable Interest, Percentage Rate | 0.75% |  |  |

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- Definition Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI https://asc.fasb.org/extlink&oid=123466204&loc=SL6031897-161870 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)) -URI https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878 + Details
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- Definition Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section 50 -Paragraph 1 -URI https://asc.fasb.org/extlink&oid=123465755&loc=d3e1835-112601 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 1E -Subparagraph (d) -URI https://asc.fasb.org/extlink&oid=123466505&loc=SL123495348-112611 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-04(a)) -URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e24072-122690 + Details
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