Income Taxes - Income Tax Provision and Effective Income Tax Rate (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Income Tax Disclosure [Abstract]
Income tax (provision) benefit	$ 27	$ (60)	$ (52)	$ (91)
Effective income tax rate	337.50%	20.60%	11.50%	16.60%