Summary of Significant Accounting Policies - Computation of Earnings (Loss) per Common Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Basic loss per share computation:
Net loss	$ (14,332)	$ (3,989)	$ (41,168)	$ (12,713)
Weighted average common shares - basic and diluted (in shares)	5,593,557	5,384,909	5,491,554	5,382,764
Basic and diluted loss per share (in dollars per share)	$ (2.56)	$ (0.74)	$ (7.50)	$ (2.36)