Note 7 - Stock-based Compensation - Restricted Stock Activity (Details) - Restricted Stock [Member] - $ / shares	3 Months Ended	12 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Outstanding, share (in shares)	40,044
Outstanding, Weighted average grant date (in dollars per share)	$ 14.89	$ 14.89
Outstanding, Average remaining contractual (Year)	2 years 146 days	2 years 219 days
Vested, share (in shares)	(85)
Vested, Weighted average grant date (in dollars per share)	$ 15.48
Outstanding, share (in shares)	39,959	40,044

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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