Equity-Based Compensation - Restricted stock (Details) - Restricted common stock $ / shares in Units, $ in Millions	9 Months Ended
	Sep. 30, 2019 USD ($) $ / shares shares
Number of unvested awards
Outstanding, beginning (in shares) | shares	664,174
Vested (in shares) | shares	(271,062)
Forfeited (in shares) | shares	(4,210)
Outstanding, end (in shares) | shares	388,902
Weighted Average Fair Value
Outstanding, beginning (in dollars per share) | $ / shares	$ 5.77
Vested (in dollars per share) | $ / shares	5.77
Forfeited (in dollars per share) | $ / shares	5.77
Outstanding, end (in dollars per share) | $ / shares	$ 5.77
Unrecognized equity based compensation expense | $	$ 1.7
Period for recognition	1 year 4 months 24 days