CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Accounts receivable, allowance for doubtful accounts	$ 5	$ 8
Class A Common Stock
Common Stock, par value (USD per share)	$ 0.01	$ 0.01
Common Stock, shares authorized (shares)	500,000,000	500,000,000
Common Stock, shares issued (shares)	58,352,497	68,897,723
Common Stock, shares outstanding (shares)	58,352,497	68,897,723
Class B Common Stock
Common Stock, par value (USD per share)	$ 0.01	$ 0.01
Common Stock, shares authorized (shares)	140,000,000	140,000,000
Common Stock, shares issued (shares)	24,727,682	25,670,684
Common Stock, shares outstanding (shares)	24,727,682	25,670,684
Consolidated VIEs
Non-recourse liabilities	$ 27	$ 27