Note 7 - Deposits (Details Textual) - USD ($) xbrli-pure in Thousands, $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Time Deposits, at or Above FDIC Insurance Limit	$ 10.0	$ 8.3
Interest-bearing Domestic Deposit, Brokered	$ 5.9	$ 33.1
Deposits, Total [Member] \| Customer Concentration Risk [Member]
Concentration Risk, Percentage	0.00%

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount of interest-bearing domestic third-party deposits placed by or through the assistance of a deposit broker, also known as brokered deposit liabilities.

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Amount of time deposit liabilities, including certificates of deposit, in denominations that meet or exceed the Federal Deposit Insurance Corporation (FDIC) insurance limit.

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