Summary of Significant Accounting Policies - Income Tax Benefits (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Summary of Significant Accounting Policies
Unrecognized Tax Benefits	$ 1,059	$ 897	$ 690
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	$ 0	$ 0