Investments (Components of other-than-temporary impairment losses recognized in earnings) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Debt Securities, Available-for-sale [Line Items]
Impairment losses (gains) recognized in earnings	$ 17	$ 20	$ 25	$ 30
Corporate and other bonds
Debt Securities, Available-for-sale [Line Items]
Impairment losses (gains) recognized in earnings	9	21	17	29
Asset-backed
Debt Securities, Available-for-sale [Line Items]
Impairment losses (gains) recognized in earnings	$ 8	$ (1)	$ 8	$ 1