Regulatory Capital Matters - Summary of Actual and Required Capital Amounts and Ratios, Exclusive of Capital Conservation Buffer (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Consolidated
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Total capital (to risk-weighted assets), Actual Amount	$ 146,641	$ 139,593
Tier 1 capital (to risk-weighted assets), Actual Amount	136,922	129,893
Common equity Tier 1 capital (to risk-weighted assets), Actual Amount	136,922	129,893
Tier 1 capital (to average assets), Actual Amount	$ 136,922	$ 129,893
Total capital (to risk-weighted assets), Actual Ratio	15.36%	16.26%
Tier 1 capital (to risk-weighted assets), Actual Ratio	14.35%	15.13%
Common equity Tier 1 capital (to risk-weighted assets), Actual Ratio	14.35%	15.13%
Tier 1 capital (to average assets), Actual Ratio	12.11%	12.88%
Bank
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Total capital (to risk-weighted assets), Actual Amount	$ 143,407	$ 139,538
Tier 1 capital (to risk-weighted assets), Actual Amount	133,688	129,838
Common equity Tier 1 capital (to risk-weighted assets), Actual Amount	133,688	129,838
Tier 1 capital (to average assets), Actual Amount	$ 133,688	$ 129,838
Total capital (to risk-weighted assets), Actual Ratio	15.03%	16.25%
Tier 1 capital (to risk-weighted assets), Actual Ratio	14.01%	15.12%
Common equity Tier 1 capital (to risk-weighted assets), Actual Ratio	14.01%	15.12%
Tier 1 capital (to average assets), Actual Ratio	11.83%	12.87%
Total capital (to risk-weighted assets), Amount, Required for Capital Adequacy Purposes	$ 76,332	$ 68,686
Tier 1 capital (to risk-weighted assets), Amount, Required for Capital Adequacy Purposes	57,249	51,514
Common equity Tier 1 capital (to risk-weighted assets), Amount, Required for Capital Adequacy Purposes	42,937	38,636
Tier 1 capital (to average assets), Amount, Required for Capital Adequacy Purposes	$ 45,212	$ 40,346
Total capital (to risk-weighted assets), Ratio, Required for Capital Adequacy Purposes	8.00%	8.00%
Tier 1 capital (to risk-weighted assets), Ratio, Required for Capital Adequacy Purposes	6.00%	6.00%
Common equity Tier 1 capital (to risk-weighted assets), Ratio, Required for Capital Adequacy Purposes	4.50%	4.50%
Tier 1 capital (to average assets), Ratio, Required for Capital Adequacy Purposes	4.00%	4.00%
Total capital (to risk-weighted assets), Amount, Minimum To be Considered "Well Capitalized"	$ 95,415	$ 85,857
Tier 1 capital (to risk-weighted assets), Amount, Minimum To be Considered "Well Capitalized"	76,332	68,686
Common equity Tier 1 capital (to risk-weighted assets), Amount, Minimum To be Considered "Well Capitalized"	62,020	55,807
Tier 1 capital (to average assets), Amount, Minimum To be Considered "Well Capitalized"	$ 56,515	$ 50,432
Total capital (to risk-weighted assets), Ratio, Minimum To be Considered "Well Capitalized"	10.00%	10.00%
Tier 1 capital (to risk-weighted assets), Ratio, Minimum To be Considered "Well Capitalized"	8.00%	8.00%
Common equity Tier 1 capital (to risk-weighted assets), Ratio, Minimum To be Considered "Well Capitalized"	6.50%	6.50%
Tier 1 capital (to average assets), Ratio, Minimum To be Considered "Well Capitalized"	5.00%	5.00%

Common equity tier one capital required for capital adequacy to risk weighted assets.

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The amount of total capital as defined in the regulations.

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

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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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Amount of Common Equity Tier One Risk-based Capital, as defined by regulatory framework.

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Percentage of Common Equity Tier One Risk-based Capital to total risk-weighted assets, as defined by regulatory framework.

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Amount of Common Equity Tier 1 Risk-based Capital required to be categorized as adequately capitalized under regulatory framework for prompt corrective action.

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Amount of Common Equity Tier 1 Risk-based Capital required to be categorized as well-capitalized under regulatory framework for prompt corrective action.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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 amount of Tier 1 Leverage Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action.

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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 amount of Tier 1 Risk Based Capital 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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