Note 1 - Organization and Significant Accounting Policies (Details Textual) - USD ($)						1 Months Ended	3 Months Ended						5 Months Ended	7 Months Ended	9 Months Ended				12 Months Ended		16 Months Ended
		Jul. 28, 2025	Feb. 24, 2025	Jun. 11, 2024	Mar. 07, 2023	Oct. 24, 2025	Sep. 30, 2025	Jun. 30, 2025	Mar. 31, 2025	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Jul. 28, 2025	Sep. 30, 2025	Sep. 30, 2025		Feb. 28, 2025	Sep. 30, 2024	Dec. 31, 2024		Jun. 30, 2024
Stock Issued During Period, Shares, New Issues (in shares)	[1]														66,690,909				31,327,547
Stock Issued During Period, Value, New Issues							$ 152,345,000	$ 139,416,000	$ 205,424,000	$ 109,891,000	$ 100,698,000	$ 13,109,000			$ 497,185,000	[1],[2]			$ 259,328,000	[1],[2]
Proceeds from Issuance of Common Stock															$ 497,185,000			$ 223,698,000
March 2023 Equity Distribution Agreement [Member]
Equity Agreement, Maximum Number of Shares Issuable					$ 250,000,000
Stock Issued During Period, Shares, New Issues (in shares)																					24,675,497
Stock Issued During Period, Value, New Issues																					$ 228,800,000
Proceeds from Issuance of Common Stock																					$ 225,000,000
June 2024 Equity Distribution Agreement [Member]
Equity Agreement, Maximum Number of Shares Issuable				$ 250,000,000
Stock Issued During Period, Shares, New Issues (in shares)																	30,513,253
Stock Issued During Period, Value, New Issues																	$ 250,000,000
Proceeds from Issuance of Common Stock																	$ 245,800,000
February 2025 Equity Distribution Agreement [Member]
Equity Agreement, Maximum Number of Shares Issuable		$ 500,000,000	$ 350,000,000
Stock Issued During Period, Shares, New Issues (in shares)														56,019,745
Stock Issued During Period, Value, New Issues														$ 420,200,000
Proceeds from Issuance of Common Stock														$ 413,500,000
Equity Agreement, Maximum Shares Issuable, Value, Increase (Decrease)													$ 150,000,000
February 2025 Equity Distribution Agreement [Member] | Subsequent Event [Member]
Stock Issued During Period, Shares, New Issues (in shares)						3,472,759
Stock Issued During Period, Value, New Issues						$ 25,000,000
Proceeds from Issuance of Common Stock						$ 24,600,000

[1] The Company has entered into 13 equity distribution agreements, 12 of which have either been terminated because all shares were sold or were replaced with a subsequent agreement.

[2] Net proceeds are net of the underwriters’ discount, if applicable, and other offering costs.