Capital Requirements and Restrictions on Retained Earnings - Summary of Actual and Required Capital Amounts and Ratios (Details) $ in Thousands	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Consolidated
Total Capital to Risk Weighted Assets
Total Capital to Risk Weighted Assets, Actual Amount	$ 462,457	$ 350,806
Total Capital to Risk Weighted Assets, Actual Ratio	0.1432	0.1251
Total Capital to Risk Weighted Assets, For Capital Adequacy Purposes Amount	$ 339,107	$ 294,407
Total Capital to Risk Weighted Assets, For Capital Adequacy Purposes Ratio	0.1050	0.1050
Tier 1 (Core) Capital to Risk Weighted Assets
Tier 1 (Core) Capital to Risk Weighted Assets, Actual Amount	$ 384,650	$ 281,333
Tier 1 (Core) Capital to Risk Weighted Assets, Actual Ratio	0.1191	0.1003
Tier 1 (Core) Capital to Risk Weighted Assets, For Capital Adequacy Purposes Amount	$ 274,516	$ 238,330
Tier 1 (Core) Capital to Risk Weighted Assets, For Capital Adequacy Purposes Ratio	0.0850	0.0850
Common equity Tier 1 to Risk Weighted Assets
Common equity Tier 1 to Risk Weighted Assets, Actual Amount	$ 306,865	$ 261,333
Common equity Tier 1 to Risk Weighted Assets, Actual Ratio	0.0950	0.0932
Common equity Tier 1 to Risk Weighted Assets, For Capital Adequacy Purposes Amount	$ 226,072	$ 196,272
Common equity Tier 1 to Risk Weighted Assets, For Capital Adequacy Purposes Ratio	7.00%	7.00%
Tier 1 (Core) Capital to Average Assets
Tier 1 (Core) Capital to Average Assets, Actual Amount	$ 384,650	$ 281,333
Tier 1 (Core) Capital to Average Assets, Actual Ratio	0.0811	0.0786
Tier 1 (Core) Capital to Average Assets, For Capital Adequacy Purposes, Amount	$ 189,728	$ 143,189
Tier 1 (Core) Capital to Average Assets, For Capital Adequacy Purposes, Ratio	0.0400	0.0400
Bank
Total Capital to Risk Weighted Assets
Total Capital to Risk Weighted Assets, Actual Amount	$ 434,598	$ 330,321
Total Capital to Risk Weighted Assets, Actual Ratio	0.1352	0.1187
Total Capital to Risk Weighted Assets, For Capital Adequacy Purposes Amount	$ 337,554	$ 292,271
Total Capital to Risk Weighted Assets, For Capital Adequacy Purposes Ratio	0.1050	0.1050
Total Capital to Risk Weighted Assets, To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	$ 321,480	$ 278,353
Total Capital to Risk Weighted Assets, To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	0.1000	0.1000
Tier 1 (Core) Capital to Risk Weighted Assets
Tier 1 (Core) Capital to Risk Weighted Assets, Actual Amount	$ 408,693	$ 312,795
Tier 1 (Core) Capital to Risk Weighted Assets, Actual Ratio	0.1271	0.1124
Tier 1 (Core) Capital to Risk Weighted Assets, For Capital Adequacy Purposes Amount	$ 273,258	$ 236,600
Tier 1 (Core) Capital to Risk Weighted Assets, For Capital Adequacy Purposes Ratio	0.0850	0.0850
Tier 1 (Core) Capital to Risk Weighted Assets, To Be Well Capitalized Under Prompt Corrective Action Provisions, Amount	$ 257,184	$ 222,682
Tier 1 (Core) Capital to Risk Weighted Assets, To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	0.0800	0.0800
Common equity Tier 1 to Risk Weighted Assets
Common equity Tier 1 to Risk Weighted Assets, Actual Amount	$ 401,314	$ 305,416
Common equity Tier 1 to Risk Weighted Assets, Actual Ratio	0.1248	0.1097
Common equity Tier 1 to Risk Weighted Assets, For Capital Adequacy Purposes Amount	$ 225,036	$ 194,847
Common equity Tier 1 to Risk Weighted Assets, For Capital Adequacy Purposes Ratio	7.00%	7.00%
Common equity Tier 1 to Risk Weighted Assets, To Be Well Capitalized Under Prompt Corrective Action Provisions, Amount	$ 208,962	$ 180,929
Common equity Tier 1 to Risk Weighted Assets, To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	6.50%	6.50%
Tier 1 (Core) Capital to Average Assets
Tier 1 (Core) Capital to Average Assets, Actual Amount	$ 408,693	$ 312,795
Tier 1 (Core) Capital to Average Assets, Actual Ratio	0.0866	0.0879
Tier 1 (Core) Capital to Average Assets, For Capital Adequacy Purposes, Amount	$ 188,690	$ 142,301
Tier 1 (Core) Capital to Average Assets, For Capital Adequacy Purposes, Ratio	0.0400	0.0400
Tier 1 (Core) Capital to Average Assets, To Be Well Capitalized Under Prompt Corrective Action Provisions, Amount	$ 235,863	$ 177,876
Tier 1 (Core) Capital to Average Assets, To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	0.0500	0.0500

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