Summary of Significant Accounting Policies - Application of New or Revised Accounting Standards (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019	Jan. 01, 2019
Summary of Significant Accounting Policies
Right-of-use asset	$ 1,932	$ 2,045	$ 3,265
Operating Lease, Liability	$ 3,331		$ 3,636