Regulatory matters - Schedule of Bank's Capital Amounts and Ratios (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Consolidated
Common equity Tier 1 capital to risk-weighted assets
Common equity Tier 1 capital to risk-weighted assets, Actual Amount	$ 205,222	$ 194,877
Common equity Tier 1 capital to risk-weighted assets, Actual Ratio	11.85%	12.49%
Common equity Tier 1 capital to risk-weighted assets, Minimum For Capital Adequacy Purposes Amount	$ 77,930	$ 70,205
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	$ 205,222	$ 194,877
Tier 1 capital to risk-weighted assets, Actual Ratio	11.85%	12.49%
Tier 1 capital to risk-weighted assets, Minimum For Capital Adequacy Purposes Amount	$ 103,906	$ 93,607
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	$ 224,182	$ 210,838
Total capital to risk-weighted assets, Actual Ratio	12.95%	13.51%
Total capital to risk-weighted assets, Minimum For Capital Adequacy Purposes Amount	$ 138,542	$ 124,810
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	$ 205,222	$ 194,877
Tier 1 capital to average assets, Actual Ratio	9.94%	10.16%
Tier 1 capital to average assets, Minimum For Capital Adequacy Purposes Amount	$ 82,564	$ 76,760
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	$ 199,450	$ 189,128
Common equity Tier 1 capital to risk-weighted assets, Actual Ratio	11.53%	12.14%
Common equity Tier 1 capital to risk-weighted assets, Minimum For Capital Adequacy Purposes Amount	$ 77,843	$ 70,120
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	$ 112,440	$ 101,284
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	$ 199,450	$ 189,128
Tier 1 capital to risk-weighted assets, Actual Ratio	11.53%	12.14%
Tier 1 capital to risk-weighted assets, Minimum For Capital Adequacy Purposes Amount	$ 103,791	$ 93,493
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	$ 138,388	$ 124,657
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	$ 218,410	$ 205,089
Total capital to risk-weighted assets, Actual Ratio	12.63%	13.16%
Total capital to risk-weighted assets, Minimum For Capital Adequacy Purposes Amount	$ 138,388	$ 124,657
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	$ 172,985	$ 155,822
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	$ 199,450	$ 189,128
Tier 1 capital to average assets, Actual Ratio	9.68%	9.88%
Tier 1 capital to average assets, Minimum For Capital Adequacy Purposes Amount	$ 82,406	$ 76,602
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	$ 103,008	$ 95,753
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 Tier 1 Common Equity Risk Based Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action.

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Tier 1 Common Equity capital divided by risk weighted assets as defined by regulations.

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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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Total Capital divided by risk weighted assets as defined in the regulations.

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

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The minimum amount of Tier 1 Leverage Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The minimum amount of Tier 1 Leverage Capital for capital adequacy purposes divided by average assets as defined in the regulations.

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Tier 1 Leverage Capital divided by average assets as defined in the regulations.

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Tier 1 Risk Based Capital as defined in the regulations.

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The minimum Tier One Capital Ratio (Tier one 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 Tier 1 Risk Based Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action.

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Tier 1 capital divided by risk weighted assets as defined by regulations.

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