Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Income tax rate	(195.10%)	(22.30%)	41.80%	74.10%
Valuation Allowance Rollforward [Roll Forward]
Balance at beginning of year			$ 2,324
Additions to valuation allowance charged to income tax expense			673
Reductions to valuation allowance credited to income tax benefit			(145)
Foreign currency translation			4
Balance at end of period	$ 2,856		2,856
Unrecognized tax benefits	74		74		$ 64
Unrecognized tax benefits that would impact the effective tax rate	41		41		40
Possible decrease in unrecognized tax benefits	8		8
Unrecognized tax benefits that would impact deferred taxes	$ 33		$ 33		$ 24