XML 92 R81.htm IDEA: XBRL DOCUMENT v3.20.2
Retirement Plans - Safe Harbor plan (Details) - USD ($)
$ in Millions
3 Months Ended 6 Months Ended 12 Months Ended
Jun. 30, 2020
Jun. 30, 2019
Jun. 30, 2020
Jun. 30, 2019
Dec. 31, 2018
Employees' savings plan          
Matching contribution by the company (as a percent)         100.00%
Expenses recognized under 401(K) plan $ 2.4 $ 1.7 $ 4.2 $ 3.0  
Discretionary matching contribution     0.375   2
Minimum          
Employees' savings plan          
Age of employees to be eligible to participate in the defined contribution plan     21 years    
Percentage of annual base compensation that participants may elect to contribute     1.00%    
Maximum          
Employees' savings plan          
Percentage of annual base compensation that participants may elect to contribute     50.00%    
Percentage of employees salary for which the company contributes a matching contribution         4.00%