Benefit Plans (Summary of non-service cost (benefit) in the condensed consolidated statements of operations (Details) - Pension Plan - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net periodic defined benefits expense (reversal of expense), excluding service cost component	$ 3	$ (14)	$ 6	$ (28)
Insurance claims and policyholder's benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net periodic defined benefits expense (reversal of expense), excluding service cost component	0	(4)	1	(8)
Other operating expenses
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net periodic defined benefits expense (reversal of expense), excluding service cost component	$ 3	$ (10)	$ 5	$ (20)