Income Taxes (Details) - Unrecognized Tax Benefits - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Reconciliation of unrecognized tax benefits [Roll Forward]
Unrecognized tax benefits, balance at January 1	$ 31	$ 6
Additions for tax positions of prior years	8	25
Reductions for tax positions of prior years	0	0
Reductions based on tax positions related to current year	0	0
Expiration of statute of limitations	(2)	0
Unrecognized tax benefits, balance at December 31	37	31	$ 6
Unrecognized tax benefits that, if recognized, would affect the annual effective tax rate	34	29
Amount of unrecognized tax benefits that are tax positions for which the ultimate deductibility is certain, but for which there is uncertainty about the timing of deductibility	3	2
Amount of interest benefit recognized on unrecognized tax benefits in income taxes	(1)	(10)	$ (33)
Accrued payment of interest balance for unrecognized tax benefits	$ 13	$ 14