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Note 10 - Intangible Assets (Details Textual) - USD ($) |  | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
Oct. 25, 2019 | Mar. 31, 2020 | Mar. 31, 2019 | Dec. 31, 2019
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life (Year) |  | 4 years |  | 4 years 73 days
Core Deposits [Member] |  |  |  |
Finite-lived Intangible Assets Acquired |  |  |  |
Core Deposits [Member] | Iowa State Savings Bank [Member] |  |  |  |
Finite-lived Intangible Assets Acquired | $ 1,891,000 |  |  |

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- Definition Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275 + Details
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- Definition Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275 + Details
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- Details
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- Details
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