Leases - Lease Costs and Maturity Analysis for Liabilities (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($) Option	Dec. 31, 2019 USD ($)
Leases
Right-of-use asset	$ 1,400
Option to extend the terms	true
Number of options to extend | Option	1
Extension term	5 years
Lease Costs
Operating lease cost	$ 419	$ 419
Lease cost	419	419
Cash paid for amounts included in the measurement of lease liabilities	$ 421	$ 412
Weighted average remaining lease terms in years - operating leases	3 years 9 months	4 years 9 months
Weighted average discount rate - operating leases	3.86%	3.86%
Maturity analysis for liabilities
Discount rate at commencement	3.86%
2021	$ 429
2022	438
2023	447
2024	340
Total undiscounted cash flows	1,654
Present value lease liability	1,536	$ 1,890
Difference between undiscounted cash flows and discounted cash flows	$ 118