Shareholders' Equity (Deficiency) (Changes in Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	$ (43)	$ 9
Other Comprehensive Loss	(4)	(95)
Other Comprehensive Income (Loss), Net of Tax	(4)	(95)
Ending balance	(47)	(86)
Foreign Currency Translation Adjustments	(4)	(95)
Currency Translation Adjustment
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(31)	7
Ending balance	(35)	(88)
Foreign Currency Translation Adjustments	(4)	(95)
Defined Benefit Pension
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(12)	2
Ending balance	(12)	2
Foreign Currency Translation Adjustments	$ 0	$ 0