Condensed Consolidated Statement of Redeemable Equity $ in Millions	USD ($)
Beginning Balance at Dec. 31, 2018	$ 37
Share-based Payments Subject to Redemption
Share-based compensation, net of issuance	(16)
Ending Balance at Mar. 31, 2019	21
Beginning Balance at Dec. 31, 2018	37
Share-based Payments Subject to Redemption
Share-based compensation, net of issuance	(12)
Ending Balance at Jun. 30, 2019	25
Beginning Balance at Mar. 31, 2019	21
Share-based Payments Subject to Redemption
Share-based compensation, net of issuance	4
Ending Balance at Jun. 30, 2019	25
Beginning Balance at Dec. 31, 2019	31
Share-based Payments Subject to Redemption
Share-based compensation, net of issuance	(8)
Ending Balance at Mar. 31, 2020	23
Beginning Balance at Dec. 31, 2019	31
Share-based Payments Subject to Redemption
Share-based compensation, net of issuance	(4)
Ending Balance at Jun. 30, 2020	27
Beginning Balance at Mar. 31, 2020	23
Share-based Payments Subject to Redemption
Share-based compensation, net of issuance	4
Ending Balance at Jun. 30, 2020	$ 27