Benefit Obligations (Pension and Other Postretirement Obligations Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Curtailment gain (loss)	$ 0	$ 0	$ 0
Lump-sum buyout payments	38	7
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Curtailment gain (loss)	0	1	$ 0
Lump-sum buyout payments	$ 0	$ 0