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Reinsurance and Indemnification - Catastrophe reinsurance (Narrative) (Details) - Catastrophe Reinsurance Program $ in Millions | 12 Months Ended
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Dec. 31, 2025 USD ($) contract Contract reinstatement
Ceded Credit Risk [Line Items] |
Catastrophe reinsurance loss amount | $ 3,100
Catastrophe reinsurance aggregate loss limit | 9,510
Two Contracts |
Ceded Credit Risk [Line Items] |
Limit of aggregate losses under aggregate excess agreement | 56
Maximum |
Ceded Credit Risk [Line Items] |
Retention amount for catastrophe reinsurance agreement contracts | 1,000
Traditional Market, Placement One |
Ceded Credit Risk [Line Items] |
Catastrophe reinsurance aggregate loss limit | 500
Retention amount for catastrophe reinsurance agreement contracts | 56
Catastrophe loss events in excess of a deductible | 50
Traditional Market |
Ceded Credit Risk [Line Items] |
Limit of aggregate losses under aggregate excess agreement | 6,080
Traditional Market | Coverage - I |
Ceded Credit Risk [Line Items] |
Catastrophe reinsurance loss limits per contract year | 3,240
Exhausting loss from catastrophes | $ 4,250
Number of reinstatements each year for each contract | reinstatement | 1
Traditional Market, Placement Two | Coverage - II |
Ceded Credit Risk [Line Items] |
Limit of aggregate losses under aggregate excess agreement | $ 336
Contracts number | Contract | 3
Traditional Market, Placement Three | Coverage - III |
Ceded Credit Risk [Line Items] |
Limit of aggregate losses under aggregate excess agreement | $ 2,500
Contracts number | Contract | 5
Term of catastrophe reinsurance agreement contract (in years) | 1 year
Insurance Linked Securities (ILS) |
Ceded Credit Risk [Line Items] |
Limit of aggregate losses under aggregate excess agreement | $ 2,700
Insurance Linked Securities (ILS) | Ten Contracts |
Ceded Credit Risk [Line Items] |
Limit of aggregate losses under aggregate excess agreement | $ 2,200
Contracts number | contract | 10
Insurance Linked Securities (ILS) | One Contract |
Ceded Credit Risk [Line Items] |
Limit of aggregate losses under aggregate excess agreement | $ 175
Contracts number | contract | 1
Insurance Linked Securities (ILS) | Two Contracts |
Ceded Credit Risk [Line Items] |
Limit of aggregate losses under aggregate excess agreement | $ 325
Contracts number | contract | 2
Insurance Linked Securities (ILS) | Coverage - II |
Ceded Credit Risk [Line Items] |
Number of reinstatements each year for each contract | reinstatement | 1
Contracts number | Contract | 2
Insurance Linked Securities (ILS) | Coverage - III |
Ceded Credit Risk [Line Items] |
Number of reinstatements each year for each contract | reinstatement | 1
Contracts number | Contract | 2

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