XML 115 R100.htm IDEA: XBRL DOCUMENT v3.10.0.1
Employee Benefit Plan (Details) - USD ($)
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Retirement Benefits [Abstract]      
Defined contribution maximum annual matching contribution per employee, percent 3.00%    
Defined contribution maximum annual discretionary contribution per employee, percent 6.00%    
Defined contribution plan, employer matching contribution, percent 3.00%    
Defined contribution plan employer matching contribution $ 700,000 $ 626,000 $ 621,000
Defined contribution plan employer discretionary contribution percent 1.00% 1.00% 1.20%
Defined contribution plan, employer discretionary contribution amount $ 180,000 $ 183,000 $ 207,000
Deferred compensation plan compensation expense 150,000 132,000 $ 124,000
Present value of future payments under the remaining deferred compensation plan liability $ 1,300,000 $ 1,100,000