Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Accounts Receivable, allowance	$ 7,247	$ 7,223
Property and equipment, accumulated depreciation	$ 12,977	$ 12,326
Common Class A
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	180,000,000	180,000,000
Common stock, shares issued	17,746,184	17,696,991
Common stock, shares outstanding	17,746,184	17,696,991
Common Class B
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	1,000	1,000
Common stock, shares issued	1	1
Common stock, shares outstanding	1	1