Collateralized Reinsurance And Trust Agreements	12 Months Ended
Collateralized Reinsurance And Trust Agreements	Dec. 31, 2022
Collateralized Reinsurance And Trust Agreements [Abstract]
Collateralized Reinsurance And Trust Agreements	8. COLLATERALIZED REINSURANCE AND TRUST AGREEMENTS Certain subsidiaries of Group have established trust agreements, which effectively use the Company’s investments as collateral, as security for assumed losses payable to certain non-affiliated ceding companies. At December 31, 2022, the total amount on deposit in trust accounts was $ 2.4 billion, which includes $ 122 million of restricted cash. At December 31, 2021, the total amount on deposit in trust accounts was $ 1.7 billion, which includes $ 190 million of restricted cash. The Company reinsures some of its catastrophe exposures with the segregated accounts of Mt. Logan Re. Mt. Logan Re is a Collateralized insurer registered in Bermuda and 100 % of the voting common shares are owned by Group. Each segregated account invests predominantly in a diversified set of catastrophe exposures, diversified by risk/peril and across different geographic regions globally. The following table summarizes the premiums and losses that are ceded by the Company to Mt. Logan Re segregated accounts and assumed by the Company from Mt. Logan Re segregated accounts. Years Ended December 31, Mt. Logan Re Segregated Accounts 2022 2021 2020 (Dollars in millions) Ceded written premiums 201 341 303 Ceded earned premiums 206 333 306 Ceded losses and LAE 191 282 241 Assumed written premiums 5 12 19 Assumed earned premiums 5 12 19 Effective April 1, 2018, the Company entered into a retroactive reinsurance transaction with one of the Mt. Logan Re segregated accounts to retrocede $ 269 million of casualty reserves held by Bermuda Re related to accident years 2002 through 2015 . As consideration for entering the agreement, the Company transferred cash of $ 252 million to the Mt. Logan Re segregated account. The maximum liability to be retroceded under the agreement will be $ 319 million. The Company will retain liability for any amounts exceeding the maximum liability. The Company will retain liability for any amounts exceeding the maximum liability. Effective July 1, 2022, the Company has commuted this reinsurance agreement with Mt. Logan segregated account. The Company entered into various collateralized reinsurance agreements with Kilimanjaro Re Limited (“Kilimanjaro”), a Bermuda based special purpose reinsurer, to provide the Company with catastrophe reinsurance coverage. These agreements are multi-year reinsurance contracts which cover named storm and earthquake events. The table below summarizes the various agreements. (Dollars in millions) Class Description Effective Date Expiration Date Limit Coverage Basis Series 2018-1 Class A-2 US, Canada, Puerto Rico – Named Storm and Earthquake Events 4/30/2018 5/5/2023 $ 63 Aggregate Series 2018-1 Class B-2 US, Canada, Puerto Rico – Named Storm and Earthquake Events 4/30/2018 5/5/2023 200 Aggregate Series 2019-1 Class A-1 US, Canada, Puerto Rico – Named Storm and Earthquake Events 12/12/2019 12/19/2023 150 Occurrence Series 2019-1 Class B-1 US, Canada, Puerto Rico – Named Storm and Earthquake Events 12/12/2019 12/19/2023 275 Aggregate Series 2019-1 Class A-2 US, Canada, Puerto Rico – Named Storm and Earthquake Events 12/12/2019 12/19/2024 150 Occurrence Series 2019-1 Class B-2 US, Canada, Puerto Rico – Named Storm and Earthquake Events 12/12/2019 12/19/2024 275 Aggregate Series 2021-1 Class A-1 US, Canada, Puerto Rico – Named Storm and Earthquake Events 4/8/2021 4/21/2025 150 Occurrence Series 2021-1 Class B-1 US, Canada, Puerto Rico – Named Storm and Earthquake Events 4/8/2021 4/21/2025 85 Aggregate Series 2021-1 Class C-1 US, Canada, Puerto Rico – Named Storm and Earthquake Events 4/8/2021 4/21/2025 85 Aggregate Series 2021-1 Class A-2 US, Canada, Puerto Rico – Named Storm and Earthquake Events 4/8/2021 4/20/2026 150 Occurrence Series 2021-1 Class B-2 US, Canada, Puerto Rico – Named Storm and Earthquake Events 4/8/2021 4/20/2026 90 Aggregate Series 2021-1 Class C-2 US, Canada, Puerto Rico – Named Storm and Earthquake Events 4/8/2021 4/20/2026 90 Aggregate Series 2022-1 Class A US, Canada, Puerto Rico – Named Storm and Earthquake Events 6/22/2022 6/22/2025 300 Aggregate Total available limit as of December 31, 2022 $ 2,063 Recoveries under these collateralized reinsurance agreements with Kilimanjaro are primarily dependent on estimated industry level insured losses from covered events, as well as, the geographic location of the events. The estimated industry level of insured losses is obtained from published estimates by an independent recognized authority on insured property losses. Currently, none of the published insured loss estimates for catastrophe events during the applicable covered periods of the various agreements have exceeded the single event retentions or aggregate retentions under the terms of the agreements that would result in a recovery. Kilimanjaro has financed the various property catastrophe reinsurance coverages by issuing catastrophe bonds to unrelated, external investors. The proceeds from the issuance of the Notes listed below are held in reinsurance trusts throughout the duration of the applicable reinsurance agreements and invested solely in U.S. government money market funds with a rating of at least “AAAm” by Standard & Poor’s. (Dollars in millions) Note Series Issue Date Maturity Date Amount Series 2018-1 Class A-2 4/30/2018 5/5/2023 $ 63 Series 2018-1 Class B-2 4/30/2018 5/5/2023 200 Series 2019-1 Class A-1 12/12/2019 12/19/2023 150 Series 2019-1 Class B-1 12/12/2019 12/19/2023 275 Series 2019-1 Class A-2 12/12/2019 12/19/2024 150 Series 2019-1 Class B-2 12/12/2019 12/19/2024 275 Series 2021-1 Class A-1 4/8/2021 4/21/2025 150 Series 2021-1 Class B-1 4/8/2021 4/21/2025 85 Series 2021-1 Class C-1 4/8/2021 4/21/2025 85 Series 2021-1 Class A-2 4/8/2021 4/20/2026 150 Series 2021-1 Class B-2 4/8/2021 4/20/2026 90 Series 2021-1 Class C-2 4/8/2021 4/20/2026 90 Series 2022-1 Class A 6/22/2022 6/22/2025 300 $ 2,063