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Note 16 - Stock-based Compensation (Details Textual) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended		6 Months Ended
	Mar. 31, 2025	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Share-Based Payment Arrangement, Expense		$ 1.3	$ 0.3	$ 1.6	$ 0.8
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Net of Forfeitures (in shares)		600,000
Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in dollars per share)				$ 25
Share-Based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount		$ 0.9		$ 0.9
Board of Directors Chairman [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Net of Forfeitures (in shares)		400,000
Non-employee Consultants [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Net of Forfeitures (in shares)		200,000
Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in dollars per share)		$ 25
Non-employee Consultants [Member] \| Share-Based Payment Arrangement, Tranche One [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested, Number of Shares (in shares)		100,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested, Weighted Average Grant Date Fair Value (in dollars per share)		$ 20
Non-employee Consultants [Member] \| Share-Based Payment Arrangement, Tranche Two [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)		3 years
Non-employee Consultants [Member] \| Share-Based Payment Arrangement, Tranche Two [Member] \| Minimum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Option, Nonvested, Weighted Average Exercise Price (in dollars per share)		$ 20		$ 20
Non-employee Consultants [Member] \| Share-Based Payment Arrangement, Tranche Two [Member] \| Maximum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Option, Nonvested, Weighted Average Exercise Price (in dollars per share)		$ 30		$ 30
Restricted Stock [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Non-Option Equity Instruments, Granted (in shares)				14,568
Restricted Stock [Member] \| Officer [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Non-Option Equity Instruments, Granted (in shares)		14,568
Restricted Common Unit Awards [Member] \| Officer [Member] \| KPH RUA [Member]
Share-Based Payment Arrangement, Expense		$ (0.1)
Share-Based Compensation Arrangement by Share-Based Payment Award, Non-Option Equity Instruments, Granted (in shares)	199,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Non-Option Equity Instruments, Forfeitures (in shares)		93,097
Share-Based Payment Arrangement, Option [Member]
Share-Based Payment Arrangement, Expense		$ 1.0
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period (Year)		10 years