Quarterly report pursuant to Section 13 or 15(d)

Share-based Compensation - Summary of Activity of Restricted Shares (Detail)

v3.21.2
Share-based Compensation - Summary of Activity of Restricted Shares (Detail)
 6 Months Ended
Jun. 30, 2021
$ / shares
shares
Restricted Stock [Member]  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Number of Restricted Shares, Opening balance | shares 1,250,000
Number of Restricted Shares, Granted | shares 1,105,700
Number of Restricted Shares, Forfeited | shares (145,600)
Number of Restricted Shares, Ending balance | shares 2,210,100
Weighted Average Grant Date Fair Value, Opening balance | $ / shares $ 15.28
Weighted Average Grant Date Fair Value, Granted | $ / shares 14.62
Weighted Average Grant Date Fair Value, Forfeited | $ / shares 14.10
Weighted Average Grant Date Fair Value, Ending balance | $ / shares $ 14.94
Performance Condition Awards [Member]  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Shares, Non-vested Opening balance | shares 950,000
Shares, Granted | shares 713,700
Shares, Forfeited | shares (85,600)
Shares, Non-vested Ending balance | shares 1,578,100
Weighted Average Grant Date Fair Value, Non-vested Opening balance | $ / shares $ 15.70
Weighted Average Grant Date Fair Value, Granted | $ / shares 16.15
Weighted Average Grant Date Fair Value, Forfeited | $ / shares 16.15
Weighted Average Grant Date Fair Value, Non-vested Ending balance | $ / shares $ 15.81
Service Condition Shares [Member]  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Shares, Non-vested Opening balance | shares 200,000
Shares, Granted | shares 52,000
Shares, Non-vested Ending balance | shares 252,000
Weighted Average Grant Date Fair Value, Non-vested Opening balance | $ / shares $ 15.70
Weighted Average Grant Date Fair Value, Granted | $ / shares 16.15
Weighted Average Grant Date Fair Value, Non-vested Ending balance | $ / shares $ 15.79
Market Condition Awards [Member]  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Shares, Non-vested Opening balance | shares 100,000
Shares, Granted | shares 340,000
Shares, Forfeited | shares (60,000)
Shares, Non-vested Ending balance | shares 380,000
Weighted Average Grant Date Fair Value, Non-vested Opening balance | $ / shares $ 10.45
Weighted Average Grant Date Fair Value, Granted | $ / shares 11.17
Weighted Average Grant Date Fair Value, Forfeited | $ / shares 11.17
Weighted Average Grant Date Fair Value, Non-vested Ending balance | $ / shares $ 10.76