Note 7 - Net Income (Loss) Per Share (Details Textual) - $ / shares shares in Thousands	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020
Share-based Payment Arrangement, Option [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount (in shares)	43	151
Share-based Payment Arrangement, Option [Member] \| Minimum [Member]
Share-based Payment Arrangement, Option, Exercise Price Range, Lower Range Limit (in dollars per share)	$ 10.37	$ 10.37
Share-based Payment Arrangement, Option [Member] \| Maximum [Member]
Share-based Payment Arrangement, Option, Exercise Price Range, Lower Range Limit (in dollars per share)		$ 17.11
Share-based Payment Arrangement, Option, Exercise Price Range, Upper Range Limit (in dollars per share)	$ 17.11
Restricted Stock, Performance-based Stock Units, and Deferred Stock Units [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount (in shares)	300	300

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=124432515&loc=d3e3550-109257

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+ 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 (g)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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