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Stockholders' Deficit - Summary of Number of PSUs granted Based on TSR and Assumptions Used to Calculate the Grant Date Fair Value Based on Total Shareholder Return (Detail) - $ / shares
12 Months Ended
May 18, 2017
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Target level for the determination of performance goals and measures   100.00%    
PSUs – Total Shareholder Return        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Target level for the determination of performance goals and measures   100.00%    
Number of units granted (in shares)   70,543 56,829 100,958
Fair value on grant date (in dollars per share)   $ 57.53 $ 43.40 $ 44.24
Expected price volatility, percent   22.86% 22.00% 25.31%
Risk-free interest rate   2.36% 2.00% 1.56%
Three-year PSU Awards        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
PSU awards performance period 3 years 3 years    
Number of units granted (in shares)   256,151    
Fair value on grant date (in dollars per share)   $ 46.87