Reinsurance (Tables)

6 Months Ended

Jun. 30, 2022

Reinsurance Disclosures [Abstract]

Reinsurance Recoverable, Credit Quality Indicator [Table Text Block]

Reinsurance Recoverables by Credit Quality Indicator
	As of June 30, 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++	$	1,873	$	—	$	—	$	1,873	$	1,860	$	—	$	—	$	1,860
A+	2,126		241		275		2,642		1,999		237		275		2,511
A	768		1		—		769		713		—		—		713
A-	48		10		—		58		37		9		—		46
B++	633		—		3		636		639		—		3		642
Below B++	20		—		—		20		20		—		—		20
Total Rated by A.M. Best	5,468		252		278		5,998		5,268		246		278		5,792
Mandatory (Assigned) and Voluntary Risk Pools	228		—		—		228		239		—		—		239
Captives	343		—		—		343		331		—		—		331
Other not rated companies	256		6		—		262		255		5		—		260
Gross Reinsurance Recoverables	6,295		258		278		6,831		6,093		251		278		6,622
Allowance for uncollectible reinsurance	(102)		(1)		(2)		(105)		(96)		(1)		(2)		(99)
Net Reinsurance Recoverables	$	6,193	$	257	$	276	$	6,726	$	5,997	$	250	$	276	$	6,523

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

Allowance for Uncollectible Reinsurance for the Three Months Ended
	June 30, 2022								June 30, 2021
	Property and Casualty		Group Benefits		Corporate		Total		Property and Casualty		Group Benefits		Corporate		Total
Beginning allowance for uncollectible reinsurance	$	96	$	1	$	2	$	99	$	95	$	1	$	2	$	98
Beginning allowance for disputed amounts	56		—		—		56		56		—		—		56
Beginning ACL	40		1		2		43		39		1		2		42
Current period provision (release)	1		—		—		1		1		—		—		1
Ending ACL	41		1		2		44		40		1		2		43
Ending allowance for disputed amounts	61		—		—		61		56		—		—		56
Ending allowance for uncollectible reinsurance	$	102	$	1	$	2	$	105	$	96	$	1	$	2	$	99

Allowance for Uncollectible Reinsurance for the Six Months Ended
	June 30, 2022								June 30, 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)	(1)		—		—		(1)		(12)		—		—		(12)
Ending ACL	41		1		2		44		40		1		2		43
Ending allowance for disputed amounts	61		—		—		61		56		—		—		56
Ending allowance for uncollectible reinsurance	$	102	$	1	$	2	$	105	$	96	$	1	$	2	$	99