Note 4 - Regulatory Matters - Actual Capital Amounts and Ratios (Details) - USD ($)	Jun. 30, 2017	Dec. 31, 2016
Tier 1 Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets	6.00%	6.00%
Tier 1 Risk Based Capital Required to be Well Capitalized	$ 6,849,000	$ 6,327,000
Tier 1 Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets	8.00%	8.00%
Common Equity Tier I Capital	$ 13,569,000	$ 12,954
Common Equity Tier I Capital to Risk Weighted Assets	15.90%	16.40%
Common Equity Tier 1 Risk Based Capital Required for Capital Adequacy	$ 3,852,000	$ 3,559
Common Equity Tier 1 Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets	4.50%	4.50%
Common Equity Tier 1 Risk Based Capital Required to be Well Capitalized	$ 5,565,000	$ 5,140
Common Equity Tier 1 Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets	6.50%	6.50%
Tier 1 Leverage Capital	$ 13,569,000	$ 12,954,000
Tier 1 Leverage Capital to Average Assets	11.50%	12.90%
Tier 1 Leverage Capital Required for Capital Adequacy	$ 4,715,000	$ 4,024,000
Tier 1 Leverage Capital Required for Capital Adequacy to Average Assets	4.00%	4.00%
Tier 1 Leverage Capital Required to be Well Capitalized	$ 5,894,000	$ 5,030,000
Tier I Leverage Capital Required to be Well Capitalized to Risk Weighted Assets	5.00%	5.00%
Capital	$ 14,639,000	$ 13,943,000
Capital to Risk Weighted Assets	17.10%	17.60%
Capital Required for Capital Adequacy	$ 6,849,000	$ 6,327,000
Capital Required for Capital Adequacy to Risk Weighted Assets	8.00%	8.00%
Capital Required to be Well Capitalized	$ 8,561,000	$ 7,908,000
Capital Required to be Well Capitalized to Risk Weighted Assets	10.00%	10.00%
Tier 1 Capital	$ 13,569,000	$ 12,954,000
Tier 1 Capital to Risk Weighted Assets	15.90%	16.40%
Tier 1 Risk Based Capital Required for Capital Adequacy	$ 5,136,000	$ 4,745,000

Common Equity Tier One Capital required for capital adequacy to risk weighted assets as defined in the regulations.

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

+ References

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- Definition

The amount of total capital as defined in the regulations.

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-SubTopic 10
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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.

+ References

No definition available.

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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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No definition available.

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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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- Definition

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 minimum Tier One Capital Ratio (Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826

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-Section 50
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-Subparagraph (c)(2)
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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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The Tier 1 capital ratio (Tier 1 capital divided by risk weighted assets) required to be categorized as "well capitalized" under the regulatory framework for prompt corrective action.

+ References

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

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