Segment and Geographic Data (Summary of Revenue and Property, Plant and Equipment by Geographical Location) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 1,371	$ 1,296	$ 1,345	$ 1,237	$ 1,386	$ 1,287	$ 1,317	$ 1,217	$ 5,249	$ 5,207	$ 4,707
Property, plant and equipment	658				656				658	656	643
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue									2,554	2,424	2,161
Property, plant and equipment	274				281				274	281	258
Europe
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue									1,380	1,449	1,335
Property, plant and equipment	249				250				249	250	259
Asia Pacific
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue									659	660	611
Property, plant and equipment	67				66				67	66	85
Other
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue									656	674	600
Property, plant and equipment	$ 68				$ 59				$ 68	$ 59	$ 41