XML 58 R48.htm IDEA: XBRL DOCUMENT v3.19.2
EQUITY - Common stock (Details) - USD ($)
$ / shares in Units, $ in Thousands
1 Months Ended 3 Months Ended 6 Months Ended
Jun. 30, 2019
Mar. 31, 2019
Jun. 30, 2019
Jun. 30, 2018
Jun. 30, 2019
Jun. 30, 2018
Class A common stock            
EQUITY            
Issuance of common stock (in shares)   403,712     423,985  
Class B common stock            
EQUITY            
Common stock retired (in shares)   254,441     260,385  
Incentive Units            
EQUITY            
Common stock exchanged (in shares) 248,142 (217,730)     (465,872)  
Issuance of common stock in connection with acquisitions (in shares)   403,712     423,985  
Fair value of the stock option grants determined with assumptions            
Compensation expense recognized     $ 4,020 $ 3,701 $ 7,039 $ 7,555
Common Stock | Class A common stock            
Changes in unvested common stock            
Outstanding at the beginning of the period         119,078  
Forfeited         (909)  
Outstanding at the end of the period 118,169   118,169   118,169  
Changes in unvested common stock, Grant Date Fair Value            
Outstanding at the beginning of the period         $ 33.00  
Forfeited         33.00  
Outstanding at the end of the period $ 33.00   $ 33.00   $ 33.00  
Common Stock | Stock options            
Changes in stock options            
Outstanding at the beginning of the period         1,401,276  
Granted         55,513  
Exercised         (24,126)  
Forfeited         22,358  
Outstanding at the end of the period 1,410,305   1,410,305   1,410,305  
Vested         478,888  
Changes in stock option, Weighted Average Exercise Price            
Outstanding at the beginning of the period         $ 31.34  
Granted         35.30  
Exercised         33.00  
Forfeited         30.33  
Outstanding at the end of the period $ 31.48   $ 31.48   31.48  
Vested         $ 33.00  
Fair value of the stock option grants determined with assumptions            
Compensation expense recognized     $ 1,158   $ 2,060  
Common Stock | Time-based stock option awards            
Fair value of the stock option grants determined with assumptions            
Expected term (in years)         6 years 3 months  
Expected stock price volatility (in percent)         28.00%  
Risk-free interest rate (in percent)         2.42%  
Weighted average grant date fair value         $ 11.67