Share-based Compensation - Share-based Compensation Cost by Award Type (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share-based compensation expense before income taxes	$ 77	$ 79	$ 85
Income tax benefit on share-based compensation expense	0	0	0
Restricted Stock
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share-based compensation expense before income taxes	49	51	53
Performance Share Units
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share-based compensation expense before income taxes	18	18	22
Stock Options
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share-based compensation expense before income taxes	$ 10	$ 10	$ 10