Note 11 - Merger (Details Textual) - Columbia Banking System, Inc. [Member] - Bank of Commerce Holdings [Member] - Forecast [Member] $ in Millions	3 Months Ended
Dec. 31, 2021 USD ($)
Business Combination, Exchange Ratio	0.40
Business Combination, Consideration Transferred, Total	$ 266.0
Business Combination, Consideration Transferred, Equity Interests Issued and Issuable	265.6
Payments to Acquire Businesses, Gross	$ 0.4

The exchange ratio of common stocks between the acquiree and acquiror in a business combination.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

+ 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.

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