Restructuring Restructuring Other Related Charges (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Restructuring Cost and Reserve [Line Items]
Charges related to voluntary termination program			$ 16
Larry D. De Shon [Member]
Restructuring Cost and Reserve [Line Items]
Other Nonrecurring Expense	$ 14
Mark J. Servodidio [Member]
Restructuring Cost and Reserve [Line Items]
Other Nonrecurring Expense	$ 4
David B. Wyshner [Member]
Restructuring Cost and Reserve [Line Items]
Other Nonrecurring Expense			$ 7
Share-based Payment Arrangement, Accelerated Cost		$ 2