Reinsurance and Indemnification- Florida Hurricane Catastrophe Fund (“FHCF”), Insurance Linked Securities (“ILS”) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2021 USD ($) contract reinstatement	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Ceded Credit Risk [Line Items]
Property-liability insurance premiums earned	$ 1,982	$ 1,154	$ 1,136
Florida Hurricane Catastrophe Fund
Ceded Credit Risk [Line Items]
Catastrophe reinsurance aggregate loss limit	1,530
Retention amount for catastrophe reinsurance agreement contracts	$ 40
Contracts number | contract	2
Reinsurance ceded amount	$ 253
Property-liability insurance premiums earned	$ 15	9	9
Florida Hurricane Catastrophe Fund | Florida Hurricane Catastrophe Fund, Contract One
Ceded Credit Risk [Line Items]
Retention percentage of reinsurance limit	90.00%
Florida Hurricane Catastrophe Fund | Florida Hurricane Catastrophe Fund, Contract Two
Ceded Credit Risk [Line Items]
Retention percentage of reinsurance limit	90.00%
Florida Hurricane Catastrophe Fund | Traditional Market
Ceded Credit Risk [Line Items]
Limit of aggregate losses under aggregate excess agreement	$ 999
Florida Hurricane Catastrophe Fund | Insurance Linked Securities (ILS)
Ceded Credit Risk [Line Items]
Limit of aggregate losses under aggregate excess agreement	$ 275
Retention percentage of reinsurance limit	73.00%
Catastrophe Reinsurance Program
Ceded Credit Risk [Line Items]
Catastrophe reinsurance aggregate loss limit	$ 5,760
Retention amount for catastrophe reinsurance agreement contracts	500
Catastrophe reinsurance loss amount	2,500
Property-liability insurance premiums earned	556	$ 425	$ 386
Catastrophe Reinsurance Program | Traditional Market
Ceded Credit Risk [Line Items]
Limit of aggregate losses under aggregate excess agreement	$ 3,730
Contracts number | contract	4
Number of reinstatements each year for each contract | reinstatement	1
Catastrophe Reinsurance Program | Insurance Linked Securities (ILS)
Ceded Credit Risk [Line Items]
Limit of aggregate losses under aggregate excess agreement	$ 1,700
National General Lender Services Standalone Program | Traditional Market
Ceded Credit Risk [Line Items]
Retention amount for catastrophe reinsurance agreement contracts	50
Loss from catastrophes	$ 190
Number of reinstatements each year for each contract | reinstatement	1
National General Reciprocal Excess Catastrophe Reinsurance Contract | Traditional Market
Ceded Credit Risk [Line Items]
Retention amount for catastrophe reinsurance agreement contracts	$ 20
Loss from catastrophes	$ 545
Number of reinstatements each year for each contract | reinstatement	1