Note 12 - Common Stock Warrants - Summary of Outstanding Warrants (Details)	Sep. 30, 2025 $ / shares shares
Number of warrant shares (in shares)	1,055,809
Warrants Expiring July 1, 2026 [Member]
Number of warrant shares (in shares)	30
Exercise price of warrants (in dollars per share) | $ / shares	$ 1,768
Common Stock	Jul. 01, 2026
Warrants Expiring November 15, 2026 [Member]
Number of warrant shares (in shares)	30
Exercise price of warrants (in dollars per share) | $ / shares	$ 1,768
Common Stock	Nov. 15, 2026
Warrants Expiring November 10, 2026 [Member]
Number of warrant shares (in shares)	102
Exercise price of warrants (in dollars per share) | $ / shares	$ 10,625
Common Stock	Nov. 10, 2026
Warrants Expiring August 9, 2027 [Member]
Number of warrant shares (in shares)	589
Exercise price of warrants (in dollars per share) | $ / shares	$ 531.25
Common Stock	Aug. 09, 2027
Warrants Expiring July 10, 2028 [Member]
Number of warrant shares (in shares)	765
Exercise price of warrants (in dollars per share) | $ / shares	$ 112.2
Common Stock	Jul. 10, 2028
Warrants Expiring July 14, 2028 [Member]
Number of warrant shares (in shares)	1,206
Exercise price of warrants (in dollars per share) | $ / shares	$ 81.6
Common Stock	Jul. 14, 2028
Warrants Expiring August 4, 2028 [Member]
Number of warrant shares (in shares)	781
Exercise price of warrants (in dollars per share) | $ / shares	$ 83.64
Common Stock	Aug. 04, 2028
Warrants Expiring May 9, 2029 [Member]
Number of warrant shares (in shares)	11,083
Exercise price of warrants (in dollars per share) | $ / shares	$ 15.9
Common Stock	May 09, 2029
Warrants Expiring May 14, 2029 [Member]
Number of warrant shares (in shares)	415,589
Exercise price of warrants (in dollars per share) | $ / shares	$ 14.45
Common Stock	May 14, 2029
Warrants Expiring June 25, 2030 [Member]
Number of warrant shares (in shares)	61,287
Exercise price of warrants (in dollars per share) | $ / shares	$ 3.04
Common Stock	Jun. 25, 2030
Warrants Expiring June 25, 2029 [Member]
Number of warrant shares (in shares)	10,000
Exercise price of warrants (in dollars per share) | $ / shares	$ 4.2
Common Stock	Jun. 25, 2029
Warrants Expiring July 31, 2030 [Member]
Number of warrant shares (in shares)	64,065
Exercise price of warrants (in dollars per share) | $ / shares	$ 3.04
Common Stock	Jul. 31, 2030
Warrants Expiring July 31, 2029 [Member]
Number of warrant shares (in shares)	11,068
Exercise price of warrants (in dollars per share) | $ / shares	$ 3.8
Common Stock	Jul. 31, 2029
Warrants Expiring August 11, 2029 [Member]
Number of warrant shares (in shares)	32,500
Exercise price of warrants (in dollars per share) | $ / shares	$ 3.64
Common Stock	Aug. 11, 2029
Warrants Expiring August 21, 2030 [Member]
Number of warrant shares (in shares)	188,842
Exercise price of warrants (in dollars per share) | $ / shares	$ 3.04
Common Stock	Aug. 21, 2030
Warrants Expiring August 21, 2029 [Member]
Number of warrant shares (in shares)	29,830
Exercise price of warrants (in dollars per share) | $ / shares	$ 3.52
Common Stock	Aug. 21, 2029
Warrants Expiring September 26, 2030 [Member]
Number of warrant shares (in shares)	195,793
Exercise price of warrants (in dollars per share) | $ / shares	$ 3.04
Common Stock	Sep. 26, 2030
Warrants Expiring September 26, 2029 [Member]
Number of warrant shares (in shares)	32,249
Exercise price of warrants (in dollars per share) | $ / shares	$ 3.26
Common Stock	Sep. 26, 2029