Annual report pursuant to Section 13 and 15(d)

Share-Based Compensation - Summary of the Changes in the Number of Outstanding Phantom Stock Shares (Details)

v3.10.0.1
Share-Based Compensation - Summary of the Changes in the Number of Outstanding Phantom Stock Shares (Details)
12 Months Ended
Dec. 31, 2018
shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]  
Balance of shares outstanding at December 31, 2017 559,627
Granted
Settled (37,510)
Forfeited (1,659)
Balance of shares outstanding at December 31, 2018 520,458
Employee Phantom Stock Plan [Member]  
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]  
Balance of shares outstanding at December 31, 2017 491,465
Granted
Settled (23,419)
Forfeited (1,659)
Balance of shares outstanding at December 31, 2018 466,387
Director Phantom Stock Plan [Member]  
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]  
Balance of shares outstanding at December 31, 2017 68,162
Granted
Settled (14,091)
Forfeited
Balance of shares outstanding at December 31, 2018 54,071