Nature of Operations and Basis of Presentation - Components of Other (Income) Expense, Net (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other (income) expense, net	$ (10)	$ (6)	$ (9)	$ 97
Non-cash pre-tax settlement charge	3		3	113
Accounting Standards Update 2017-07
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other components of net periodic benefit cost	(5)	(7)	(15)	96
Net (gain) loss from investments	(5)	1	6	1
Other (income) expense, net	$ (10)	$ (6)	$ (9)	$ 97