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Stock-Based Compensation - Additional Information (Detail) - USD ($)
$ in Millions
1 Months Ended 12 Months Ended
Nov. 30, 2019
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Performance Share Unit Plan [Member]        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
PSU/RSU performance cycles   3 years    
Number of trading days   50 days    
Compensation cost recognized   $ 8 $ 4 $ 2
Tax benefits related to compensation cost   2 1 $ 1
Unrecognized compensation cost   $ 4 $ 6  
Weighted-average period expected to be recognized   2 years    
Restricted Stock Units (RSUs) [Member]        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
PSU/RSU performance cycles 3 years      
Number of trading days 50 days