Regulatory Capital Requirements - Actual and Required Capital Amounts and Ratios (Details) - Common equity tier 1 capital - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Jan. 01, 2015
Common Equity Tier 1 Capital [Abstract]
Common Equity Tier 1 Capital to risk-weighted assets	$ 149,223	$ 142,018
Common Equity Tier 1 Capital required for adequacy purposes	38,275	37,501
Common Equity Tier 1 Capital required to be categorized as well capitalized	55,286	54,169
Tier One Risk Based Capital [Abstract]
Tier 1 Capital	149,223	142,018
Tier 1 Capital required for adequacy purposes	51,034	50,002
Tier 1 Capital required to be categorized as well capitalized	$ 68,045	$ 66,669
Risk Based Ratios [Abstract]
Common Equity Tier 1 Capital to risk-weighted assets, percentage	17.54%	17.04%
Common Equity Tier 1 Capital required for adequacy purposes, percentage	4.50%	4.50%	4.50%
Common Equity Tier 1 Capital required to be categorized as well capitalized, percentage	6.50%	6.50%
Tier 1 Capital to risk-weighted assets, percentage	17.54%	17.04%
Tier 1 Capital required for adequacy purposes, percentage	6.00%	6.00%	6.00%
Tier 1 Capital required to be categorized as well capitalized, percentage	8.00%	8.00%	6.00%
Total Capital to risk-weighted assets, percentage	18.70%	18.21%
Total Capital required for adequacy purposes, percentage	8.00%	8.00%	8.00%
Total Capital required to be categorized as well capitalized, percentage	10.00%	10.00%
Capital [Abstract]
Total Capital	$ 159,058	$ 151,781
Total Capital required for adequacy purposes	68,045	66,669
Total Capital required to be categorized as well capitalized	85,056	83,336
Tier One Leverage Capital [Abstract]
Tier 1 Leverage Capital	149,223	142,018
Tier 1 Leverage Capital required for adequacy purposes	49,103	49,509
Tier 1 Leverage Capital required to be categorized as well capitalized	$ 61,379	$ 61,887
Leverage Ratios [Abstract]
Tier 1 Leverage Capital to adjusted average assets, percentage	12.16%	11.47%
Tier 1 Leverage Capital required for adequacy purposes, percentage	4.00%	4.00%	4.00%
Tier 1 Leverage Capital required to be categorized as well capitalized, percentage	5.00%	5.00%	5.00%

Tier One Common Equity Capital

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Tier One Common Equity Capital Required For Capital Adequacy To Risk Weighted Assets

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Tier One Common Equity Capital Required To Be Well Capitalized

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

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