Note 5 - Derivative and Other Hedging Instruments - Schedule of Interest Rate Swaps (Details) - Interest Rate Swap [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
Notional amount	$ 5,858.3	$ 3,516.8
Average fixed pay rate	3.53%	2.78%
Average receive rate	3.87%	4.54%
Average maturity (Year)	4 years 3 months 18 days	5 years 6 months
One to Five Years [Member]
Notional amount	$ 4,162.5	$ 1,450.0
Average fixed pay rate	3.38%	1.69%
Average receive rate	3.87%	4.58%
Average maturity (Year)	3 years 2 months 12 days	3 years 4 months 24 days
More Than Five Years [Member]
Notional amount	$ 1,695.8	$ 2,066.8
Average fixed pay rate	3.87%	3.55%
Average receive rate	3.87%	4.52%
Average maturity (Year)	7 years 1 month 6 days	7 years