Condensed Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - $ / shares $ / shares in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Common stock, par value (in dollars per share)	$ 0	$ 0	$ 0
Common stock, shares issued (in shares)	26,998,363	26,953,363	25,473,363
Common stock, shares outstanding (in shares)	26,998,363	26,953,363	25,473,363
Common stock, shares authorized	Unlimited	Unlimited	Unlimited

Face amount per share of no-par value common stock.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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Indicates that the number of common shares permitted to be issued by an entity's charter and bylaws is unlimited. The acceptable value is "Unlimited".

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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