Note 2 - Common Stock Outstanding and Earnings Per Share (Details Textual) - USD ($) $ in Millions		3 Months Ended	9 Months Ended
Jan. 31, 2019	Sep. 30, 2019	Sep. 30, 2019
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares	1,834,142		1,834,142
Payments to Acquire Businesses, Gross	$ 15.3
Stock Repurchase Program, Authorized Amount		$ 1.0	$ 1.0
Stock Repurchased During Period, Shares		0
Merchants Holding Company [Member] \| Bank of Commerce [Member]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	10.00%

Number of shares of equity interests issued or issuable to acquire entity.

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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

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Amount of stock repurchase plan authorized.

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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