Regulatory matters - Schedule of Bank's Capital Amounts and Ratios (Details) $ in Thousands	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Consolidated
Common equity Tier 1 capital to risk-weighted assets
Common equity Tier 1 capital to risk-weighted assets, Actual Amount	$ 250,397	$ 237,280
Common equity Tier 1 capital to risk-weighted assets, Actual Ratio	12.16	11.90
Common equity Tier 1 capital to risk-weighted assets, Minimum For Capital Adequacy Purposes Amount	$ 92,631	$ 89,717
Common equity Tier 1 capital to risk-weighted assets, Minimum For Capital Adequacy Purposes Ratio	4.50	4.50
Tier 1 capital to risk-weighted assets
Tier 1 capital to risk-weighted assets, Actual Amount	$ 250,397	$ 237,280
Tier 1 capital to risk-weighted assets, Actual Ratio	12.16	11.90
Tier 1 capital to risk-weighted assets, Minimum For Capital Adequacy Purposes Amount	$ 123,508	$ 119,623
Tier 1 capital to risk-weighted assets, Minimum For Capital Adequacy Purposes Ratio	6.00	6.00
Total capital to risk-weighted assets
Total capital to risk-weighted assets, Actual Amount	$ 310,741	$ 259,957
Total capital to risk-weighted assets, Actual Ratio	15.10	13.04
Total capital to risk-weighted assets, Minimum For Capital Adequacy Purposes Amount	$ 164,677	$ 159,497
Total capital to risk-weighted assets, Minimum For Capital Adequacy Purposes Ratio	8.00	8.00
Tier 1 capital to average assets
Tier 1 capital to average assets, Actual Amount	$ 250,397	$ 237,280
Tier 1 capital to average assets, Actual Ratio	9.28	10.14
Tier 1 capital to average assets, Minimum For Capital Adequacy Purposes Amount	$ 107,878	$ 93,633
Tier 1 capital to average assets, Minimum For Capital Adequacy Purposes Ratio	4.00	4.00
Peoples Bank
Common equity Tier 1 capital to risk-weighted assets
Common equity Tier 1 capital to risk-weighted assets, Actual Amount	$ 282,104	$ 231,685
Common equity Tier 1 capital to risk-weighted assets, Actual Ratio	13.73	11.64
Common equity Tier 1 capital to risk-weighted assets, Minimum For Capital Adequacy Purposes Amount	$ 92,461	$ 89,576
Common equity Tier 1 capital to risk-weighted assets, Minimum For Capital Adequacy Purposes Ratio	4.50	4.50
Common equity Tier 1 capital to risk-weighted assets, Minimum to be Well Capitalized under Prompt Corrective Action Provisions Amount	$ 133,554	$ 129,387
Common equity Tier 1 capital to risk-weighted assets, Minimum to be Well Capitalized under Prompt Corrective Action Provisions Ratio	6.50	6.50
Tier 1 capital to risk-weighted assets
Tier 1 capital to risk-weighted assets, Actual Amount	$ 282,104	$ 231,685
Tier 1 capital to risk-weighted assets, Actual Ratio	13.73	11.64
Tier 1 capital to risk-weighted assets, Minimum For Capital Adequacy Purposes Amount	$ 123,281	$ 119,434
Tier 1 capital to risk-weighted assets, Minimum For Capital Adequacy Purposes Ratio	6.00	6.00
Tier 1 capital to risk-weighted assets, Minimum to be Well Capitalized under Prompt Corrective Action Provisions Amount	$ 164,374	$ 159,246
Tier 1 capital to risk-weighted assets, Minimum to be Well Capitalized under Prompt Corrective Action Provisions Ratio	8.00	8.00
Total capital to risk-weighted assets
Total capital to risk-weighted assets, Actual Amount	$ 307,807	$ 254,362
Total capital to risk-weighted assets, Actual Ratio	14.98	12.78
Total capital to risk-weighted assets, Minimum For Capital Adequacy Purposes Amount	$ 164,374	$ 159,246
Total capital to risk-weighted assets, Minimum For Capital Adequacy Purposes Ratio	8.00	8.00
Total capital to risk-weighted assets, Minimum to be Well Capitalized under Prompt Corrective Action Provisions Amount	$ 205,468	$ 199,057
Total capital to risk-weighted assets, Minimum to be Well Capitalized under Prompt Corrective Action Provisions Ratio	10.00	10.00
Tier 1 capital to average assets
Tier 1 capital to average assets, Actual Amount	$ 282,104	$ 231,685
Tier 1 capital to average assets, Actual Ratio	10.08	9.91
Tier 1 capital to average assets, Minimum For Capital Adequacy Purposes Amount	$ 111,891	$ 93,508
Tier 1 capital to average assets, Minimum For Capital Adequacy Purposes Ratio	4.00	4.00
Tier 1 capital to average assets, Minimum to be Well Capitalized under Prompt Corrective Action Provisions Amount	$ 139,864	$ 116,884
Tier 1 capital to average assets, Minimum to be Well Capitalized under Prompt Corrective Action Provisions Ratio	5.00	5.00

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