Note 12 - Fair Value Measurements - Fair Value Hierarchy for Cash Equivalents, Marketable Securities and Derivative Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Contingent consideration	$ 720	$ 720
Warrant liabilities	5,492	0
Total liabilities	120,308	87,728
Financial instrument liability		825
Front Line Power Seller Notes [Member]
Debt Instrument, Fair Value Disclosure	68,501
Seller Financed Notes Payable - Front Line Power Acquisition [Member]
Debt Instrument, Fair Value Disclosure	40,085	86,183
Syndicated Term Note [Member]
Debt Instrument, Fair Value Disclosure	844
Prepaid Advance Agreement [Member]
Debt Instrument, Fair Value Disclosure	4,666
Fair Value, Inputs, Level 1 [Member]
Contingent consideration	0	0
Warrant liabilities	0
Total liabilities	0	0
Financial instrument liability		0
Fair Value, Inputs, Level 1 [Member] \| Front Line Power Seller Notes [Member]
Debt Instrument, Fair Value Disclosure	0
Fair Value, Inputs, Level 1 [Member] \| Seller Financed Notes Payable - Front Line Power Acquisition [Member]
Debt Instrument, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 1 [Member] \| Syndicated Term Note [Member]
Debt Instrument, Fair Value Disclosure	0
Fair Value, Inputs, Level 1 [Member] \| Prepaid Advance Agreement [Member]
Debt Instrument, Fair Value Disclosure	0
Fair Value, Inputs, Level 2 [Member]
Contingent consideration	0	0
Warrant liabilities	0
Total liabilities	73,167	86,183
Financial instrument liability		0
Fair Value, Inputs, Level 2 [Member] \| Front Line Power Seller Notes [Member]
Debt Instrument, Fair Value Disclosure	68,501
Fair Value, Inputs, Level 2 [Member] \| Seller Financed Notes Payable - Front Line Power Acquisition [Member]
Debt Instrument, Fair Value Disclosure	0	86,183
Fair Value, Inputs, Level 2 [Member] \| Syndicated Term Note [Member]
Debt Instrument, Fair Value Disclosure	0
Fair Value, Inputs, Level 2 [Member] \| Prepaid Advance Agreement [Member]
Debt Instrument, Fair Value Disclosure	4,666
Fair Value, Inputs, Level 3 [Member]
Contingent consideration	720	720
Warrant liabilities	5,492
Total liabilities	47,141	1,545
Financial instrument liability		825
Fair Value, Inputs, Level 3 [Member] \| Front Line Power Seller Notes [Member]
Debt Instrument, Fair Value Disclosure	0
Fair Value, Inputs, Level 3 [Member] \| Seller Financed Notes Payable - Front Line Power Acquisition [Member]
Debt Instrument, Fair Value Disclosure	40,085	$ 0
Fair Value, Inputs, Level 3 [Member] \| Syndicated Term Note [Member]
Debt Instrument, Fair Value Disclosure	844
Fair Value, Inputs, Level 3 [Member] \| Prepaid Advance Agreement [Member]
Debt Instrument, Fair Value Disclosure	$ 0

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

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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Fair value of financial and nonfinancial obligations.

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