CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY - 9 months ended Sep. 30, 2018 - USD ($) shares in Thousands, $ in Thousands	Class A Common Stock Common stock	Class B Common Stock Common stock	Members' Equity (Deficit)	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Non-controlling Interest	Total
Balance at the beginning of the period at Dec. 31, 2017			$ (36,299)			$ 82		$ (36,217)
Statement of Stockholders'/Members' Equity
Member distributions prior to IPO			(26,000)					(26,000)
Net income prior to IPO and reorganization			13,648					13,648
Effect of IPO and Reorganization	$ 265		$ 48,651	$ 71,196			$ 130,861	250,973
Effect of IPO and Reorganization (shares)	26,450	48,440
Member distribution after IPO							(5,848)	(5,848)
Effect of Follow-on Offering	$ 112			24,472			(25,293)	(709)
Effect of Follow-on Offering (in shares)	11,197	(11,197)
Additional paid-in capital related to tax receivable agreement				28,552				28,552
Other comprehensive (loss)						(870)		(870)
Stock-based compensation				3,384				3,384
Net income after IPO and Reorganization					$ 34,759		63,191	97,950
Balance at the end of the period at Sep. 30, 2018	$ 377			$ 127,604	$ 34,759	$ (788)	$ 162,911	$ 324,863
Balance at the end of the period (shares) at Sep. 30, 2018	37,647	37,243