Net Income (Loss) Per Share Attributable to Class A Common Shareholders - Schedule of Calculations of Basic and Diluted Net Income (Loss) Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Numerator:
Net income (loss) attributable to holders of shares of Class A common stock—basic	$ 32,449	$ 19,205	$ 101,464	$ 54,213
Class A Common Stock
Numerator:
Net income (loss) attributable to holders of shares of Class A common stock—basic	32,449	19,205	101,464	54,213
Add (deduct) dilutive effect of:
Net income (loss) attributable to holders of shares of Class A common stock—diluted	$ 32,449	$ 19,205	$ 101,464	$ 54,213
Denominator:
Weighted average shares of Class A common stock outstanding—basic	45,203,781	32,505,940	41,211,843	29,094,514
Add (deduct) dilutive effect of:
Weighted average number of incremental shares issuable from unvested restricted stock, RSUs and stock options, as calculated using the treasury stock method	7,937,417	7,278,693	7,962,061	6,778,333
Weighted average shares of Class A common stock outstanding—diluted	53,141,198	39,784,633	49,173,904	35,872,847
Net income (loss) per share attributable to holders of shares of Class A common stock
Basic (in dollars per share)	$ 0.72	$ 0.59	$ 2.46	$ 1.86
Diluted (in dollars per share)	$ 0.61	$ 0.48	$ 2.06	$ 1.51