Note 2 - Fair Value of Financial Instruments - Summary of the Fair Value of Marketable Securities (Details) $ in Thousands	Dec. 31, 2022 USD ($)
Due within One Year, Amortized Cost	$ 260,629
Due within One Year	259,376
Due after One Year through Two Years, Amortized Cost	43,528
Due after One Year through Two Years	42,272
Mature over Two Years, Amortized Cost	2,694
Mature over Two Years	2,631
Amortized Cost	322,012
Available-for-Sale, Total	319,306
Asset-Backed Securities [Member]
Amortized Cost	15,161
Available-for-Sale, Total	$ 15,027

Represents fair value of available-for-sale for debt maturities after year two.

No definition available.

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Represents fair value of available-for-sale securities for debt maturities for next twelve months.

+ References

No definition available.

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- Definition

Represents fair value of debt maturities for available-for-sale securities through year one to year two.

+ References

No definition available.

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- Definition

Amortized cost 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 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27198-111563

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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))
-URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 45
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-Topic 320
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-Section 50
-Paragraph 2
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-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563

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