Regulatory Capital Matters - Summary of Actual and Required Capital Amounts and Ratios, Exclusive of Capital Conservation Buffer (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Capital conservation buffer	1.875%	1.25%	0.625%
Consolidated
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Total capital (to risk-weighted assets), Actual Amount	$ 139,593	$ 100,713
Tier 1 capital (to risk-weighted assets), Actual Amount	129,893	91,510
Common equity Tier 1 capital (to risk-weighted assets), Actual Amount	129,893	91,510
Tier 1 capital (to average assets), Actual Amount	$ 129,893	$ 91,510
Total capital (to risk-weighted assets), Actual Ratio	16.26%	13.49%
Tier 1 capital (to risk-weighted assets), Actual Ratio	15.13%	12.26%
Common equity Tier 1 capital (to risk-weighted assets), Actual Ratio	15.13%	12.26%
Tier 1 capital (to average assets), Actual Ratio	12.88%	10.46%
Total capital (to risk-weighted assets), Amount, Required for Capital Adequacy Purposes		$ 59,729
Tier 1 capital (to risk-weighted assets), Amount, Required for Capital Adequacy Purposes		44,797
Common equity Tier 1 capital (to risk-weighted assets), Amount, Required for Capital Adequacy Purposes		33,597
Tier 1 capital (to average assets), Amount, Required for Capital Adequacy Purposes		$ 35,009
Capital conservation buffer		8.00%
Tier 1 capital (to risk-weighted assets), Ratio, Required for Capital Adequacy Purposes		6.00%
Common equity Tier 1 capital (to risk-weighted assets), Ratio, Required for Capital Adequacy Purposes		4.50%
Tier 1 capital (to average assets), Ratio, Required for Capital Adequacy Purposes		4.00%
Bank
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Total capital (to risk-weighted assets), Actual Amount	$ 139,538	$ 100,648
Tier 1 capital (to risk-weighted assets), Actual Amount	129,838	91,445
Common equity Tier 1 capital (to risk-weighted assets), Actual Amount	129,838	91,445
Tier 1 capital (to average assets), Actual Amount	$ 129,838	$ 91,445
Total capital (to risk-weighted assets), Actual Ratio	16.25%	13.48%
Tier 1 capital (to risk-weighted assets), Actual Ratio	15.12%	12.25%
Common equity Tier 1 capital (to risk-weighted assets), Actual Ratio	15.12%	12.25%
Tier 1 capital (to average assets), Actual Ratio	12.87%	10.45%
Total capital (to risk-weighted assets), Amount, Required for Capital Adequacy Purposes	$ 68,686	$ 59,726
Tier 1 capital (to risk-weighted assets), Amount, Required for Capital Adequacy Purposes	51,514	44,795
Common equity Tier 1 capital (to risk-weighted assets), Amount, Required for Capital Adequacy Purposes	38,636	33,596
Tier 1 capital (to average assets), Amount, Required for Capital Adequacy Purposes	$ 40,346	$ 35,007
Capital conservation buffer	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"	$ 85,857	$ 74,658
Tier 1 capital (to risk-weighted assets), Amount, Minimum To be Considered "Well Capitalized"	68,686	59,726
Common equity Tier 1 capital (to risk-weighted assets), Amount, Minimum To be Considered "Well Capitalized"	55,807	48,528
Tier 1 capital (to average assets), Amount, Minimum To be Considered "Well Capitalized"	$ 50,432	$ 43,759
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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Common equity tier one capital required to be well capitalized 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 minimum amount of Tier 1 Leverage Capital for capital adequacy purposes divided by average assets as defined in the regulations.

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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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The amount of Tier 1 Leverage Capital required to be categorized as well capitalized divided by average assets as defined in 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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