Income Taxes - Contingency (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2019	Mar. 31, 2020
Contingencies
Deferred income taxes	$ 13	$ 13	$ 16
Indirect tax credits | Foreign | Brazil
Contingencies
Deferred income taxes	8	8
Indirect tax credits | Foreign | Brazil | Maximum
Contingencies
Amount of indirect tax credits expected to receive		86
Indirect tax credits | Foreign | Brazil | Minimum
Contingencies
Amount of indirect tax credits expected to receive		$ 22
Indirect tax credits | Foreign | Brazil | Other operating income, net
Contingencies
Future tax credits	$ 22