v3.26.1
Note 11 - Other Comprehensive Income (Loss) - Reconciliation of Accumulated Comprehensive Income (Loss) (Details) - USD ($)
 3 Months Ended 9 Months Ended
Jun. 30, 2026
Mar. 31, 2026
Dec. 31, 2025
Jun. 30, 2025
Mar. 31, 2025
Dec. 31, 2024
Jun. 30, 2026
Jun. 30, 2025
Balance $ 124,084,505 $ 116,431,475 $ 113,552,790 $ 117,833,223 $ 111,761,089 $ 108,136,775 $ 113,552,790 $ 108,136,775
Other comprehensive income 199,072 135,495 (126,917) (263,406) (373,852) 222,428 207,650 (414,830)
Balance 122,874,179 124,084,505 116,431,475 116,261,318 117,833,223 111,761,089 122,874,179 116,261,318
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member]                
Balance     664,568       664,568  
Other comprehensive income             225,092  
Balance 889,660           889,660  
Accumulated Defined Benefit Plans Adjustment, Net Gain (Loss) Attributable to Parent [Member]                
Balance     (402,836)       (402,836)  
Other comprehensive income             (17,442)  
Balance (420,278)           (420,278)  
AOCI Attributable to Parent [Member]                
Balance 270,310 134,815 261,732 1,175,147 1,548,999 1,326,571 261,732 1,326,571
Other comprehensive income 199,072 135,495 (126,917) (263,406) (373,852) 222,428 207,650  
Balance $ 469,382 $ 270,310 $ 134,815 $ 911,741 $ 1,175,147 $ 1,548,999 $ 469,382 $ 911,741