Claim, Claim Adjustment Expense and Future Policy Benefit Reserves (International - Net prior year claim and allocated claim adjustment expense reserve development) (Details) - International - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Liability for Claims and Claims Adjustment Expense [Line Items]
Commercial	$ (35)	$ (2)	$ (8)
Specialty	36	3	37
Other	1	(3)	(8)
Total pretax (favorable) unfavorable development	$ 2	$ (2)	$ 21