Other Operating Expenses and Other Expenses - Summary of Other Expenses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Other Operating Expenses And Other Expenses [Abstract]
Employee severance	$ 1,055	$ 1,386	$ 147
Income on leased building the Company was previously deemed to own for accounting purposes	0	(623)	(248)
Legal and professional services related to secondary share offerings	0	337	535
Other	0	0	105
Impairment of intangible asset	0	200	0
Total	$ 1,055	$ 1,300	$ 539