Reinsurance (Tables)

3 Months Ended

Mar. 31, 2024

Reinsurance Disclosures [Abstract]

Reinsurance Recoverable, Credit Quality Indicator [Table Text Block]

Reinsurance Recoverables by Credit Quality Indicator
	As of March 31, 2024								As of December 31, 2023
	P&C		Group Benefits		Corporate		Total		P&C		Group Benefits		Corporate		Total
A.M. Best Financial Strength Rating
A++	$	2,394	$	—	$	—	$	2,394	$	2,398	$	—	$	—	$	2,398
A+	2,034		250		243		2,527		2,030		251		241		2,522
A	787		1		—		788		810		1		—		811
A-	647		5		—		652		653		5		—		658
B++	4		—		3		7		2		—		3		5
Below B++	22		—		—		22		22		—		—		22
Total Rated by A.M. Best	5,888		256		246		6,390		5,915		257		244		6,416
Mandatory (Assigned) and Voluntary Risk Pools	203		—		—		203		208		—		—		208
Captives	353		—		—		353		353		—		—		353
Other not rated companies	243		6		—		249		226		4		—		230
Gross Reinsurance Recoverables	6,687		262		246		7,195		6,702		261		244		7,207
Allowance for uncollectible reinsurance	(98)		(1)		(2)		(101)		(100)		(1)		(2)		(103)
Net Reinsurance Recoverables	$	6,589	$	261	$	244	$	7,094	$	6,602	$	260	$	242	$	7,104

Reinsurance Recoverable, Allowance for Credit Loss [Table Text Block]

Allowance for Uncollectible Reinsurance for the Three Months Ended
	Three Months Ended March 31,
	2024		2023
P&C beginning allowance for uncollectible reinsurance	$	100	$	102
Beginning allowance for disputed amounts	57		60
P&C beginning ACL	43		42
Current period provision	1		2
P&C ending ACL	44		44
Ending allowance for disputed amounts	54		58
P&C ending allowance for uncollectible reinsurance	98		102
Group Benefits allowance for uncollectible reinsurance	1		1
Corporate allowance for uncollectible reinsurance	2		2
Total allowance for uncollectible reinsurance	$	101	$	105