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Shareholders Capital - Additional Information (Detail) - USD ($)
$ in Millions
 1 Months Ended 12 Months Ended
Jan. 31, 2020
Dec. 31, 2019
Disclosure Of Classes Of Share Capital [Line Items]    
Number of share purchase and cancel   16,000,000
Percentage of share purchase and cancel   10.00%
Purchase and cancel of shares   $ 26
Events After Reporting Period [Member]    
Disclosure Of Classes Of Share Capital [Line Items]    
Number of share purchase and cancel 3,000,000  
Purchase and cancel of shares $ 5  
Top of Range [Member]    
Disclosure Of Classes Of Share Capital [Line Items]    
Number of share purchase and cancel   29,170,887