Investments (Components of other-than-temporary impairment losses recognized in earnings) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Impairment (gains) losses recognized in earnings	$ 31	$ 111	$ 44
Corporate and other bonds
Debt Securities, Available-for-sale [Line Items]
Impairment (gains) losses recognized in earnings	11	87	33
Asset-backed
Debt Securities, Available-for-sale [Line Items]
Impairment (gains) losses recognized in earnings	$ 20	$ 24	$ 11