Annual report pursuant to Section 13 and 15(d)

Benefit Plan (Details)

v3.10.0.1
Benefit Plan (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Retirement Benefits [Abstract]      
Voluntary employer matching contributions $ 4,778 $ 4,038 $ 2,270