Note 17 - Derivative Financial Instruments (Details Textual) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Derivative, Gain (Loss) on Derivative, Net, Total	$ 800,000	$ 200,000	$ 2,300,000	$ 0
Commitment to Originate Mortgage Loans [Member]
Notional Amount of Forward Rate Commitments and Futures Contracts to Hedge against Mortgage Servicing Rights	191,800,000		191,800,000
No Commitment to Originate Mortgage Loans [Member]
Loans Receivable Held-for-sale, Net, Not Part of Disposal Group, Mortgage	10,600,000		10,600,000
Forward Sales of Mortgage Backed Securities [Member]
Notional Amount of Forward Rate Commitments and Futures Contracts to Hedge against Mortgage Servicing Rights	$ 110,000,000		$ 110,000,000

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=109980867&loc=SL5618551-113959

+ Details

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- Definition

Amount, after allowance for bad debt, of mortgage loan receivables held-for-sale that are not part of a disposal group. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

+ Details

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- Details

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- Details

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- Details

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