Reinsurance (Tables)

3 Months Ended

Mar. 31, 2022

Reinsurance Disclosures [Abstract]

Reinsurance Recoverable, Credit Quality Indicator [Table Text Block]

Reinsurance Recoverables by Credit Quality Indicator
	As of March 31, 2022								As of December 31, 2021
	Property and Casualty		Group Benefits		Corporate		Total		Property and Casualty		Group Benefits		Corporate		Total
A.M. Best Financial Strength Rating
A++	$	1,877	$	—	$	—	$	1,877	$	1,860	$	—	$	—	$	1,860
A+	2,056		236		273		2,565		1,999		237		275		2,511
A	743		1		—		744		713		—		—		713
A-	33		9		—		42		37		9		—		46
B++	633		—		3		636		639		—		3		642
Below B++	20		—		—		20		20		—		—		20
Total Rated by A.M. Best	5,362		246		276		5,884		5,268		246		278		5,792
Mandatory (Assigned) and Voluntary Risk Pools	234		—		—		234		239		—		—		239
Captives	340		—		—		340		331		—		—		331
Other not rated companies	261		6		—		267		255		5		—		260
Gross Reinsurance Recoverables	6,197		252		276		6,725		6,093		251		278		6,622
Allowance for uncollectible reinsurance	(96)		(1)		(2)		(99)		(96)		(1)		(2)		(99)
Net Reinsurance Recoverables	$	6,101	$	251	$	274	$	6,626	$	5,997	$	250	$	276	$	6,523

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

Allowance for Uncollectible Reinsurance for the Three Months Ended
	March 31, 2022								March 31, 2021
	Property and Casualty		Group Benefits		Corporate		Total		Property and Casualty		Group Benefits		Corporate		Total
Beginning allowance for uncollectible reinsurance	$	96	$	1	$	2	$	99	$	105	$	1	$	2	$	108
Beginning allowance for disputed amounts	54		—		—		54		53		—		—		53
Beginning ACL	42		1		2		45		52		1		2		55
Current period provision (release)	(2)		—		—		(2)		(13)		—		—		(13)
Ending ACL	40		1		2		43		39		1		2		42
Ending allowance for disputed amounts	56		—		—		56		56		—		—		56
Ending allowance for uncollectible reinsurance	$	96	$	1	$	2	$	99	$	95	$	1	$	2	$	98