Regulatory Capital - Schedule of actual amount and capital ratios of company and bank (Details) - Bank $ in Thousands	Jun. 30, 2020 USD ($)
Total Capital to Risk Weighted Assets
Total Capital to Risk Weighted Assets, Actual Capital Amount	$ 173,270
Total Capital to Risk Weighted Assets, Actual Capital Ratio	0.145
Total Capital to Risk Weighted Assets, For Capital Adequacy Purposes, Amount	$ 123,451
Total Capital to Risk Weighted Assets To be Categorized as Well-capitalized, Amount	123,938
Tier 1 Capital to Risk Weighted Assets
Tier 1 Capital to Risk Weighted Assets, Actual Capital Amount	$ 158,302
Tier 1 Capital to Risk Weighted Asset, Actual Capital Ratio	0.133
Tier One Risk Based Capital Required for Capital Adequacy	$ 82,109
Tier 1 Capital to Risk Weighted Assets, To be Categorized As Well Capitalized, Amount	99,151
Tier 1 Capital to Average Assets
Tier 1 Capital to Average Assets, Actual Capital Amount	$ 158,302
Tier 1 Capital to Average Asset, Actual Capital Ratio	0.092
Tier 1 Capital to Average Assets, For Capital Adequacy Purposes, Amount	$ 57,253
Tier 1 Capital to Risk Weighted Assets, To be Categorized As Well Capitalized, Amount	$ 71,566
Minimum
Total Capital to Risk Weighted Assets
Total Capital to Risk Weighted Assets, For Capital Adequacy Purposes, Ratio	0.08625
Total Capital to Risk Weighted Assets To be Categorized as Well-capitalized, Ratio	0.100
Tier 1 Capital to Risk Weighted Assets
Tier 1 Capital to Risk Weighted Assets, For Capital Adequacy Purposes, Ratio	0.06625
Tier 1 Capital to Risk Weighted Assets, To be Categorized As Well Capitalized, Ratio	0.080
Tier 1 Capital to Average Assets
Tier 1 Capital to Average Assets, For Capital Adequacy Purposes, Ratio	0.040
Tier One Leverage Capital Required to be Well Capitalized to Average Assets	0.050
Common stock
Tier 1 Capital to Risk Weighted Assets
Tier 1 Capital to Risk Weighted Assets, Actual Capital Amount	$ 158,302
Tier 1 Capital to Risk Weighted Asset, Actual Capital Ratio	0.133
Tier One Risk Based Capital Required for Capital Adequacy	$ 63,518
Tier 1 Capital to Risk Weighted Assets, To be Categorized As Well Capitalized, Amount	$ 80,560
Common stock | Minimum
Tier 1 Capital to Risk Weighted Assets
Tier 1 Capital to Risk Weighted Assets, For Capital Adequacy Purposes, Ratio	0.05125
Tier 1 Capital to Risk Weighted Assets, To be Categorized As Well Capitalized, Ratio	0.065