Accounts Payable and Accrued Expenses (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Accounts Payable and Accrued Liabilities
Accounts payable	$ 3,507	$ 8,262
Accrued expenses	3,091	3,237
Accrued compensation	9,681	7,631
Accounts Payable and Accrued Expenses	$ 16,279	$ 19,130