Regulatory Capital Matters - Actual and Required Capital Amounts and Ratios (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Amount
Common equity Tier 1 capital to RWA	$ 388,199	$ 367,096
Total capital to RWA	487,966	449,325
Tier 1 (Core) Capital to RWA	388,199	367,096
Tier 1 (core) capital to average assets	388,199	367,096
Common equity Tier 1 capital to RWA	146,711	135,598
Total capital to RWA	260,819	241,064
Tier 1 (core) capital to RWA	195,614	180,798
Tier 1 (core) capital to average assets	$ 151,456	$ 167,553
Ratio
Common equity Tier 1 capital to RWA	11.90%	12.20%
Total capital to RWA	15.00%	14.90%
Tier 1 (core) capital to RWA	11.90%	12.20%
Tier 1 (core) capital to average assets	10.30%	8.80%
Common equity Tier 1 capital to RWA	4.50%	4.50%
Total capital to RWA	8.00%	8.00%
Tier 1 (core) capital to RWA	6.00%	6.00%
Tier 1 (core) capital to average assets	4.00%	4.00%
Bank
Amount
Common equity Tier 1 capital to RWA	$ 441,348	$ 421,335
Total capital to RWA	482,183	444,871
Tier 1 (Core) Capital to RWA	441,348	421,335
Tier 1 (core) capital to average assets	441,348	421,335
Common equity Tier 1 capital to RWA	146,491	135,613
Total capital to RWA	260,429	241,090
Tier 1 (core) capital to RWA	195,322	180,818
Tier 1 (core) capital to average assets	151,255	167,420
Common equity Tier 1 capital to RWA	211,599	195,886
Total Capital to RWA	325,536	301,363
Tier 1 (core) capital to RWA	260,429	241,090
Tier 1 (core) capital to average assets	$ 189,069	$ 209,275
Ratio
Common equity Tier 1 capital to RWA	13.60%	14.00%
Total capital to RWA	14.80%	14.80%
Tier 1 (core) capital to RWA	13.60%	14.00%
Tier 1 (core) capital to average assets	11.70%	10.10%
Common equity Tier 1 capital to RWA	4.50%	4.50%
Total capital to RWA	8.00%	8.00%
Tier 1 (core) capital to RWA	6.00%	6.00%
Tier 1 (core) capital to average assets	4.00%	4.00%
Common equity Tier 1 capital to RWA	6.50%	6.50%
Total capital to RWA	10.00%	10.00%
Tier 1 (core) capital to RWA	8.00%	8.00%
Tier 1 (core) capital to average assets	5.00%	5.00%

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

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Common equity tier one risk based capital required to be well capitalized to risk weighted assets.

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Compliance with Regulatory Capital Requirements Under Banking Regulations, Capital

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Compliance with Regulatory Capital Requirements under Banking Regulations, Ratios

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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 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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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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