Annual report pursuant to Section 13 and 15(d)

Share-Based Compensation - Additional Information (Detail)

v3.8.0.1
Share-Based Compensation - Additional Information (Detail) - USD ($)
$ / shares in Units, $ in Thousands
1 Months Ended 12 Months Ended
Mar. 31, 2017
Dec. 31, 2017
Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Share-based compensation expense for vested shares employees and directors   $ 23,019 $ 24,495
Settlement of bonuses accrued     $ 2,000
Unrecognized compensation expense   $ 147,200  
Granted (in dollars per share)   $ 2.72  
Share-based payments (in shares)   2,015,000 0
Exercised (in shares)   0 0
Performance-based      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Number of awards to vest   19,600,000  
Restricted Stock      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Total grant date fair value of restricted stock vested   $ 3,700  
Stock Options      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Vesting period (in years)   3 years  
2016 Omnibus Compensation Incentive Plan      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Number of common stock authorized for issuance   40,000,000  
Granted (in dollars per share) $ 11.88