Accrued Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Accrued Liabilities
Accrued payroll and related employee expenses	$ 3,954	$ 4,040
Accrued employee performance bonus	3,920	7,137
Accrued Interest	4,951	5,058
Operating and financing lease liability (current portion)	4,494	521
Other	5,501	7,097
Total accrued expenses	$ 22,820	$ 23,853