Regulatory Matters (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Summary of State Bank's actual capital amounts and ratios
Tier I Capital to average assets actual amount	$ 83,807	$ 74,183
Tier I Capital to average assets for capital adequacy purposes amount	34,477	31,875
Tier I Capital to average assets to be well capitalized under prompt corrective action procedures amount	43,097	39,844
Tier I Common equity capital to risk-weighted assets actual amount	83,807	74,183
Tier I Common equity capital to risk-weighted assets for capital adequacy purposes	35,786	32,477
Tier I Common equity capital to risk-weighted assets to be well capitalized under prompt corrective action procedures amount	51,691	46,912
Tier I Capital to risk-weighted assets actual amount	83,807	74,183
Tier I Capital to risk-weighted assets for capital adequacy purposes	47,715	43,303
Tier I Capital to risk-weighted assets to be well capitalized under prompt corrective action procedures	63,620	57,738
Total Risk-based capital to risk-weighted assets actual amount	91,737	81,908
Total Risk-based capital to risk-weighted assets for capital adequacy purposes amount	63,620	57,738
Total Risk-based capital to risk-weighted assets to be well capitalized under prompt corrective action procedures amount	$ 79,524	$ 72,172
Tier I Capital to average assets actual ratio	9.72%	9.31%
Tier I Capital to average assets for capital adequacy purposes ratio	4.00%	4.00%
Tier I Capital to average assets to be well capitalized under prompt corrective action procedures ratio	5.00%	5.00%
Tier I Common equity capital to risk-weighted assets actual ratio	10.54%	10.28%
Tier I Common equity capital to risk-weighted assets for capital adequacy purposes	4.50%	4.50%
Tier I Common equity capital to risk-weighted assets to be well capitalized under prompt corrective action procedures ratio	6.50%	6.50%
Tier I Capital to risk-weighted assets actual ratio	10.54%	10.28%
Tier I Capital to risk-weighted assets for capital adequacy purposes ratio	6.00%	6.00%
Tier I Capital to risk-weighted assets to be well capitalized under prompt corrective action procedures ratio	8.00%	8.00%
Total Risk-based capital to risk-weighted assets actual ratio	11.54%	11.35%
Total Risk-based capital to risk-weighted assets capital adequacy purposes ratio	8.00%	8.00%
Total Risk-based capital to risk-weighted assets to be well capitalized under prompt corrective action procedures ratio	10.00%	10.00%

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The amount of total capital as defined in the regulations.

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

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