Other Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Jan. 01, 2019	Dec. 31, 2018
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Cash surrender value of corporate-owned life insurance policies	$ 4,020		$ 3,596
Deferred commissions	17,920		15,530
Restricted cash	658		661
Operating lease assets	10,592
Prepaid expenses, deposits and other	3,952		3,212
Total other assets	$ 37,142	$ 35,482	$ 22,999