Note 12 - Stockholders' Equity (Details Textual) - USD ($) $ / shares in Units, $ in Millions			9 Months Ended
	Sep. 08, 2023	Feb. 03, 2023	Sep. 30, 2023	Sep. 30, 2022	Jun. 13, 2023
Proceeds from Issuance of Common Stock			$ 254.4	$ 115.0
Private Placement, Tranche 1 [Member]
Equity Offering, Maximum Shares to be Issued (in shares)					8,026,165
Equity Offering, Price Per Share (in dollars per share)					$ 4.9837
Equity Offering, Maximum Amount					$ 40.0
Private Placement, Tranche 2 [Member]
Equity Offering, Maximum Shares to be Issued (in shares)					22,072,103
Equity Offering, Price Per Share (in dollars per share)					$ 4.9837
Equity Offering, Maximum Amount					$ 110.0
Private Placement, Tranche 3 [Member]
Stock Issued During Period, Shares, New Issues (in shares)	14,802,055
Equity Offering, Maximum Amount					$ 69.4
Equity Offering, Maximum Percentage of Outstanding Common Stock					17.50%
HGC NEXT INV LLC [Member]
Stock Issued During Period, Shares, New Issues (in shares)		5,835,277
Share Price (in dollars per share)		$ 5.998
Proceeds from Issuance of Common Stock		$ 35.0