Note 17 - Derivative Financial Instruments (Details Textual) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Derivative, Gain (Loss) on Derivative, Net, Total	$ 1.0	$ 0.9
Commitment to Originate Mortgage Loans [Member]
Notional Amount of Forward Rate Commitments and Futures Contracts to Hedge against Mortgage Servicing Rights	221.0
No Commitment to Originate Mortgage Loans [Member]
Financing Receivable, Held-for-Sale, Not Part of Disposal Group, after Valuation Allowance, Ending Balance	43.7
Forward Sales of Mortgage Backed Securities [Member]
Notional Amount of Forward Rate Commitments and Futures Contracts to Hedge against Mortgage Servicing Rights	$ 162.0

The notional amount of forward rate commitments and futures contracts to hedge against mortgage servicing rights.

No definition available.

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- Definition

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5618551-113959

+ Details

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- Definition

Amount, after valuation allowance, of financing receivable held for sale and not part of disposal group. Excludes loan covered under loss sharing agreement and loan classified as investment in debt security.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=121593590&loc=d3e4428-111522

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 310
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=120238483&loc=d3e48678-111004

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- Details

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- Details

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- Details

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