Fair Value of Financial Instruments and Fair Value Measurements - Quantitative Information for Financial Instruments Measured at Fair Value (Details) $ in Thousands	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other real estate owned	$ 1,006	$ 1,320	$ 1,841
Fair Value, Nonrecurring
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impaired loans	5,939	5,985
Other real estate owned	1,006	1,320
Level 3 | Fair Value, Nonrecurring
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impaired loans	5,939	5,985
Other real estate owned	$ 1,006	$ 1,320
Level 3 | Fair Value, Nonrecurring | Minimum | Measurement Input, Appraised Value
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impaired loans, weighted average measurement input	0.25	0
Other real estate, weighted average measurement input	0	0
Level 3 | Fair Value, Nonrecurring | Maximum | Measurement Input, Appraised Value
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impaired loans, weighted average measurement input	1	0.20
Other real estate, weighted average measurement input	0.20	0.20