Share-Based Compensation - Vested Restricted Shares (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total fair value of restricted shares vested	$ 1	$ 4	$ 8
Share-Settled RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total fair value of restricted shares vested	15	11	5
Share-settled PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total fair value of restricted shares vested	$ 3	$ 0	$ 0