Restructuring - Narrative (Details) $ in Millions	9 Months Ended
	Sep. 30, 2020 USD ($) position	Dec. 31, 2019 USD ($)
2020 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Workforce reduction | position	90
Restructuring charges paid	$ 12
Increase (decrease) in restructuring reserve	(5)
Restructuring reserve balance	$ 7
2019 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Workforce reduction | position	300
Restructuring charges paid	$ 13
Restructuring reserve balance	$ 5	$ 18