Investments (Components of other-than-temporary impairment losses recognized in earnings) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Impairment (gains) losses recognized in earnings	$ 10	$ 6
Corporate and other bonds
Debt Securities, Available-for-sale [Line Items]
Impairment (gains) losses recognized in earnings	8	7
Asset-backed
Debt Securities, Available-for-sale [Line Items]
Impairment (gains) losses recognized in earnings	$ 2	$ (1)