Note 11 - Fair Value Measurements (Details Textual) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2023	Jun. 30, 2022
OCI, Debt Securities, Available-for-Sale, Transfer from Held-to-Maturity, Gain (Loss), before Adjustment and Tax	$ (0.2)	$ (0.3)
Debt Security, Corporate, Non-US [Member]
Debt Instrument, Interest Rate, Stated Percentage			8.75%
PEMEX [Member]
Accounts Receivable, before Allowance for Credit Loss, Current	$ 7.8	$ 7.8	$ 8.6

Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
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Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 210
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
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- Definition

Amount, before tax and adjustment, of unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to 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
-Topic 320
-SubTopic 10
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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