Note 1 - Organization and Significant Accounting Policies (Details Textual) - USD ($) $ / shares in Units, $ in Thousands			3 Months Ended				4 Months Ended	6 Months Ended		12 Months Ended
	Mar. 07, 2023	Oct. 29, 2021	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022	Jun. 30, 2022	Oct. 28, 2021	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022	Aug. 30, 2022
Stock Issued During Period, Shares, New Issues (in shares)					3,885,048			7,447,953,000		3,885,048,000
Stock Issued During Period, Value, New Issues			$ 47,355	$ 31,657	$ 40,580			$ 79,012		$ 40,580
Proceeds from Issuance of Common Stock								79,012	$ 0
Direct Operating Costs			$ 173			$ 183		$ 338	508
Common Stock, Par or Stated Value Per Share (in dollars per share)			$ 0.01		$ 0.01			$ 0.01		$ 0.01	$ 0.01
Reclassification to Conform To Current Period [Member]
Direct Operating Costs						$ 400			$ 700
June 2021 Equity Distribution Agreement [Member]
Equity Agreement, Maximum Number of Shares Issuable (in shares)							250,000,000
October 2021 Equity Distribution Agreement [Member]
Stock Issued During Period, Shares, New Issues (in shares)		9,742,188
Stock Issued During Period, Value, New Issues		$ 151,800
Proceeds from Issuance of Common Stock		$ 149,300
March 2023 Equity Distribution Agreement [Member]
Equity Agreement, Maximum Number of Shares Issuable (in shares)	250,000,000
Stock Issued During Period, Shares, New Issues (in shares)								4,757,953
Stock Issued During Period, Value, New Issues								$ 48,100
Proceeds from Issuance of Common Stock								$ 47,400