Note 9 - Mortgage Banking Derivatives - Amount and Fair Value of Mortgage Banking Derivatives (Details) - USD ($)	Mar. 31, 2020	Jan. 01, 2020	Dec. 31, 2019
Interest Rate Contract [Member]
Derivative, amount	$ 16,667,000		$ 10,307,000
Derivative, fair value	503,000		328,000
Forward Contracts [Member]
Derivative, amount	22,000,000		14,000,000
Derivative, fair value	$ (385,000)	$ (385,000)	$ (23,000)

Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226000-175313

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