Note 8 - Securities Sold Under Agreements to Repurchase (Details Textual) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Securities Sold under Agreements to Repurchase, Total	$ 16,013,000	$ 13,058,000
Assets Sold under Agreements to Repurchase, Carrying Amount	$ 22,033,000	$ 21,764,000
Securities Sold Under Agreements to Repurchase, Term	2 years

Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Name:	us-gaap_SecuritiesSoldUnderAgreementsToRepurchase
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant