Basis of Presentation - Reconciliation of Basic and Diluted Earnings per Share (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Numerator - Basic
Net income (loss) attributable to common stockholders	$ 14,058,000	$ (21,685,000)	$ (35,394,000)	$ (63,636,000)
Less: allocation to participating securities	(5,494,000)	0	0	0
Net income (loss) allocated to common stockholders - basic	8,564,000	(21,685,000)	(35,394,000)	(63,636,000)
Numerator - Diluted
Net income (loss) allocated to common stockholders - basic	8,564,000	(21,685,000)	(35,394,000)	(63,636,000)
Restricted stock unit compensation gain, net of tax	(80,000)	0	0	0
Net income (loss) allocated to common stockholders - diluted	$ 8,484,000	$ (21,685,000)	$ (35,394,000)	$ (63,636,000)
Denominator
Weighted average number of common shares - basic (in shares)	24,933,853	24,599,744	24,852,994	24,598,816
Restricted stock units converted under the treasury stock method (in shares)	397,957	0	0	0
Weighted average number of common shares - diluted (in shares)	25,331,810	24,599,744	24,852,994	24,598,816
Earnings per share
Basic (in dollars per share)	$ 0.34	$ (0.88)	$ (1.42)	$ (2.59)
Diluted (in dollars per share)	$ 0.33	$ (0.88)	$ (1.42)	$ (2.59)