Fair Value Measurements - Level 3 Measurement Inputs (Details) - Nonrecurring $ in Thousands	Sep. 30, 2020 USD ($)	Dec. 31, 2019 USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Total impaired loans	$ 1,383	$ 1,678
Significant Unobservable Inputs (Level 3)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Total impaired loans	1,383	1,678
SBA property
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Total impaired loans	251	116
SBA property | Significant Unobservable Inputs (Level 3)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Total impaired loans	251	116
Commercial lines of credit
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Total impaired loans	1,120	1,562
Commercial lines of credit | Significant Unobservable Inputs (Level 3)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Total impaired loans	$ 1,120	$ 1,562
Commercial lines of credit | Minimum | Sales comparison approach | Significant Unobservable Inputs (Level 3) | Adjustment for differences between the comparable estate sales
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impairment loans, measurement input	(0.10)	(0.04)
Commercial lines of credit | Minimum | Income approach | Significant Unobservable Inputs (Level 3) | Adjustment for differences in net operating income expectations
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impairment loans, measurement input		(0.04)
Commercial lines of credit | Maximum | Sales comparison approach | Significant Unobservable Inputs (Level 3) | Adjustment for differences between the comparable estate sales
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impairment loans, measurement input	0.13	0.26
Commercial lines of credit | Maximum | Income approach | Significant Unobservable Inputs (Level 3) | Adjustment for differences in net operating income expectations
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impairment loans, measurement input		(0.11)
Commercial lines of credit | Weighted Average | Sales comparison approach | Significant Unobservable Inputs (Level 3) | Adjustment for differences between the comparable estate sales
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impairment loans, measurement input	(0.021)	0.0086
Commercial lines of credit | Weighted Average | Income approach | Significant Unobservable Inputs (Level 3) | Adjustment for differences in net operating income expectations
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impairment loans, measurement input		(0.0620)
Commercial lines of credit | Weighted Average | Income approach | Significant Unobservable Inputs (Level 3) | Capitalization rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impairment loans, measurement input	0.050	0.05
SBA commercial term
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Total impaired loans	$ 12
SBA commercial term | Significant Unobservable Inputs (Level 3)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Total impaired loans	$ 12