Regulatory matters - Schedule of Bank's Capital Amounts and Ratios (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Consolidated
Common equity Tier 1 capital to risk-weighted assets
Common equity Tier 1 capital to risk-weighted assets, Actual Amount	$ 237,280	$ 221,024
Common equity Tier 1 capital to risk-weighted assets, Actual Ratio	11.90%	11.95%
Common equity Tier 1 capital to risk-weighted assets, Minimum For Capital Adequacy Purposes Amount	$ 89,717	$ 83,241
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	$ 237,280	$ 221,024
Tier 1 capital to risk-weighted assets, Actual Ratio	11.90%	11.95%
Tier 1 capital to risk-weighted assets, Minimum For Capital Adequacy Purposes Amount	$ 119,623	$ 110,988
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	$ 259,957	$ 242,403
Total capital to risk-weighted assets, Actual Ratio	13.04%	13.10%
Total capital to risk-weighted assets, Minimum For Capital Adequacy Purposes Amount	$ 159,497	$ 147,984
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	$ 237,280	$ 221,024
Tier 1 capital to average assets, Actual Ratio	10.14%	10.03%
Tier 1 capital to average assets, Minimum For Capital Adequacy Purposes Amount	$ 93,633	$ 88,119
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	$ 231,685	$ 215,027
Common equity Tier 1 capital to risk-weighted assets, Actual Ratio	11.64%	11.64%
Common equity Tier 1 capital to risk-weighted assets, Minimum For Capital Adequacy Purposes Amount	$ 89,576	$ 83,144
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	$ 129,387	$ 120,097
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	$ 231,685	$ 215,027
Tier 1 capital to risk-weighted assets, Actual Ratio	11.64%	11.64%
Tier 1 capital to risk-weighted assets, Minimum For Capital Adequacy Purposes Amount	$ 119,434	$ 110,859
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	$ 159,246	$ 147,811
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	$ 254,362	$ 236,406
Total capital to risk-weighted assets, Actual Ratio	12.78%	12.80%
Total capital to risk-weighted assets, Minimum For Capital Adequacy Purposes Amount	$ 159,246	$ 147,811
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	$ 199,057	$ 184,764
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	$ 231,685	$ 215,027
Tier 1 capital to average assets, Actual Ratio	9.91%	9.78%
Tier 1 capital to average assets, Minimum For Capital Adequacy Purposes Amount	$ 93,508	$ 87,969
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	$ 116,884	$ 109,962
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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Tier 1 Common Equity Risk Based Capital as defined in the regulations.

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The Tier One minimum Common Equity Capital Ratio ( Tier one Common Equity capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The amount of total capital as defined in the regulations.

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The minimum Total risk based capital ratio (total capital divided by risk weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The amount of Total Capital required to be categorized as well as capitalized under the regulatory framework for prompt corrective action.

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The Total risk based capital ratio (total capital divided by risk weighted assets) required to be categorized as "well capitalized", in the regulatory framework for prompt corrective action.

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Tier 1 Leverage Capital as defined in the regulations. Also called Core Capital.

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Tier 1 Risk Based Capital as defined in the regulations.

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