Restructuring Other Related Charges (Details) $ in Millions	9 Months Ended
	Sep. 30, 2020 USD ($) Employee	Sep. 30, 2019 USD ($)
Restructuring Cost and Reserve [Line Items]
Charges related to voluntary termination program	$ 18
Charges related to voluntary termination program, Number of Positions Eliminated | Employee	400
Restructuring and Related Cost, Expected Cost Remaining	$ 2	$ 12
Larry D. De Shon [Member]
Restructuring Cost and Reserve [Line Items]
Other Nonrecurring Expense	1
Michael K. Tucker [Member]
Restructuring Cost and Reserve [Line Items]
Other Nonrecurring Expense	2
Mark J. Servodidio [Member]
Restructuring Cost and Reserve [Line Items]
Other Nonrecurring Expense	$ 3	$ 3