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Note 5 - Fair Value Measurements - Assets Measured on a Recurring Basis (Details) - Fair Value, Recurring [Member] - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Assets measured on a recurring basis	$ 105,669	$ 98,938
US Government Agencies Debt Securities [Member]
Assets measured on a recurring basis	1,999	7,471
Subordinated Debt Securities [Member]
Assets measured on a recurring basis	4,150
US States and Political Subdivisions Debt Securities [Member]
Assets measured on a recurring basis	79,641	73,093
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Assets measured on a recurring basis	19,251	17,758
Debt Securities [Member]
Assets measured on a recurring basis	105,041	98,322
Equity Securities [Member]
Assets measured on a recurring basis	628	616
Fair Value, Inputs, Level 1 [Member]
Assets measured on a recurring basis	628	616
Fair Value, Inputs, Level 1 [Member] | US Government Agencies Debt Securities [Member]
Assets measured on a recurring basis
Fair Value, Inputs, Level 1 [Member] | Subordinated Debt Securities [Member]
Assets measured on a recurring basis
Fair Value, Inputs, Level 1 [Member] | US States and Political Subdivisions Debt Securities [Member]
Assets measured on a recurring basis
Fair Value, Inputs, Level 1 [Member] | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Assets measured on a recurring basis
Fair Value, Inputs, Level 1 [Member] | Debt Securities [Member]
Assets measured on a recurring basis
Fair Value, Inputs, Level 1 [Member] | Equity Securities [Member]
Assets measured on a recurring basis	628	616
Fair Value, Inputs, Level 2 [Member]
Assets measured on a recurring basis	105,041	98,322
Fair Value, Inputs, Level 2 [Member] | US Government Agencies Debt Securities [Member]
Assets measured on a recurring basis	1,999	7,471
Fair Value, Inputs, Level 2 [Member] | Subordinated Debt Securities [Member]
Assets measured on a recurring basis	4,150
Fair Value, Inputs, Level 2 [Member] | US States and Political Subdivisions Debt Securities [Member]
Assets measured on a recurring basis	79,641	73,093
Fair Value, Inputs, Level 2 [Member] | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Assets measured on a recurring basis	19,251	17,758
Fair Value, Inputs, Level 2 [Member] | Debt Securities [Member]
Assets measured on a recurring basis	105,041	98,322
Fair Value, Inputs, Level 2 [Member] | Equity Securities [Member]
Assets measured on a recurring basis
Fair Value, Inputs, Level 3 [Member]
Assets measured on a recurring basis
Fair Value, Inputs, Level 3 [Member] | US Government Agencies Debt Securities [Member]
Assets measured on a recurring basis
Fair Value, Inputs, Level 3 [Member] | Subordinated Debt Securities [Member]
Assets measured on a recurring basis
Fair Value, Inputs, Level 3 [Member] | US States and Political Subdivisions Debt Securities [Member]
Assets measured on a recurring basis
Fair Value, Inputs, Level 3 [Member] | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Assets measured on a recurring basis
Fair Value, Inputs, Level 3 [Member] | Debt Securities [Member]
Assets measured on a recurring basis
Fair Value, Inputs, Level 3 [Member] | Equity Securities [Member]
Assets measured on a recurring basis

X

- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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- Details

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