Leases - Balance Sheet Classification of Operating Lease Right-of-use Assets and Lease Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Assets
Operating lease right-of-use assets	$ 193	$ 511
Liabilities
Operating lease liabilities	$ 196	$ 517
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Other assets	Other assets
Operating Lease, Liability, Statement of Financial Position [Extensible List]	Other liabilities	Other liabilities