Employee Benefit Plans - 401(K) Saving And Retirement Plan (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Employee Benefit Plan Compensation      
Compensation cost $ 7,400 $ 9,000 $ 9,000
Non Employee Director      
Employee Benefit Plan Compensation      
Granted (in shares) 107,389 148,077 105,479
Compensation cost $ 261 $ 276 $ 267
Savings And Retirement Plan 401 K      
401(K) Savings & Retirement Plan      
Percent of salary employee is permitted to contribute 100.00%    
Vesting period 3 years    
Common stock, shares issued 633,827    
Total expense (including issuance of shares) $ 1,800 $ 1,600 $ 1,400