Summary of Significant Accounting Policies - Leases (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Jan. 01, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease right-of-use asset	$ 2,798	$ 3,400
Operating lease liabilities	$ 3,700	$ 4,469
Adjustments Due to ASC 842
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease right-of-use asset			$ 3,982
Operating lease liabilities			$ 5,190