Note 2 - Fair Value Measurement - Financial Assets and Liabilities on Recurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Marketable debt securities	$ 23,035
Fair Value, Recurring [Member]
Assets	43,111	$ 63,873
Contingent consideration - business combinations	3,515	10,027
Debt	7,551	7,215
Liabilities	11,066	17,242
Fair Value, Recurring [Member] \| US Government Agencies Debt Securities [Member]
Marketable debt securities	10,335
Fair Value, Recurring [Member] \| Corporate Debt Securities [Member]
Marketable debt securities	11,515
Fair Value, Recurring [Member] \| Other Debt Obligations [Member]
Marketable debt securities	1,185
Fair Value, Recurring [Member] \| Money Market Funds [Member]
Cash equivalents	17,086	63,873
Fair Value, Recurring [Member] \| Corporate Debt Securities, Cash Equivalents [Member]
Cash equivalents	2,242
Fair Value, Recurring [Member] \| Non-US Government Agency Securities, Cash Equivalents [Member]
Cash equivalents	748
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Assets	27,421	63,873
Contingent consideration - business combinations	0	0
Debt	0	0
Liabilities	0	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| US Government Agencies Debt Securities [Member]
Marketable debt securities	10,335
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Corporate Debt Securities [Member]
Marketable debt securities	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Other Debt Obligations [Member]
Marketable debt securities	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Money Market Funds [Member]
Cash equivalents	17,086	63,873
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Corporate Debt Securities, Cash Equivalents [Member]
Cash equivalents	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Non-US Government Agency Securities, Cash Equivalents [Member]
Cash equivalents	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Assets	15,690	0
Contingent consideration - business combinations	0	0
Debt	7,551	7,215
Liabilities	7,551	7,215
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| US Government Agencies Debt Securities [Member]
Marketable debt securities	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Corporate Debt Securities [Member]
Marketable debt securities	11,515
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Other Debt Obligations [Member]
Marketable debt securities	1,185
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Money Market Funds [Member]
Cash equivalents	0	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Corporate Debt Securities, Cash Equivalents [Member]
Cash equivalents	2,242
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Non-US Government Agency Securities, Cash Equivalents [Member]
Cash equivalents	748
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Assets	0	0
Contingent consideration - business combinations	3,515	10,027
Debt	0	0
Liabilities	3,515	10,027
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| US Government Agencies Debt Securities [Member]
Marketable debt securities	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Corporate Debt Securities [Member]
Marketable debt securities	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Other Debt Obligations [Member]
Marketable debt securities	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Money Market Funds [Member]
Cash equivalents	0	$ 0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Corporate Debt Securities, Cash Equivalents [Member]
Cash equivalents	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Non-US Government Agency Securities, Cash Equivalents [Member]
Cash equivalents	$ 0

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
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-Section 45
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 45
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- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
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- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

No definition available.

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- Definition

Fair value of financial and nonfinancial obligations.

+ References

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

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