Note 16 - Subsequent Event (Details Textual)	1 Months Ended	6 Months Ended
Jul. 31, 2020 $ / shares shares	Jun. 30, 2020 shares
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)		453,000
Subsequent Event [Member] \| MPSUs 2020 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Maximum Percentage Allowed	500.00%
Share-based Compensation Arrangement by Share-based Payment Award, Number of Price Targets	5
Share Based Compensation Arrangement By Share Based Payment Award, Post-vesting Sales Restriction Period (Year)	1 year
Subsequent Event [Member] \| MPSUs 2020 [Member] \| Vest on July, 2023 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	75.00%
Subsequent Event [Member] \| MPSUs 2020 [Member] \| Vest on July 20, 2024 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	25.00%
Subsequent Event [Member] \| MPSUs 2020 [Member] \| Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award, Stock Price Target (in dollars per share) \| $ / shares	$ 260
Subsequent Event [Member] \| MPSUs 2020 [Member] \| Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award, Stock Price Target (in dollars per share) \| $ / shares	$ 300
Subsequent Event [Member] \| MPSUs 2020 [Member] \| Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)	43,000
Subsequent Event [Member] \| MPSUs 2020 [Member] \| Key Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)	2,000

The maximum number of equity awards an employee may receive as a percentage of the target number.

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- Definition

Number of individual price target.

+ References

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- Definition

Represents post-vesting sales restriction for share based compensation arrangement by share based payment award.

+ References

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- Definition

Represents stock price target for share based compensation arrangement by share based compensation award.

+ References

No definition available.

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

Percentage of vesting of award under share-based payment arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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