Note 4 - Derivatives and Other Hedging Instruments - Schedule of Interest Rate Swaps (Details) - Interest Rate Swap [Member] - USD ($) $ in Millions	6 Months Ended	12 Months Ended
	Jun. 30, 2023	Dec. 31, 2022
Notional amount	$ 2,151.5	$ 1,400.0
Average fixed pay rate	2.13%	1.39%
Average receive rate	5.23%	4.41%
Average maturity (Year)	6 years 1 month 6 days	5 years 7 months 6 days
One to Five Years [Member]
Notional amount	$ 500.0	$ 500.0
Average fixed pay rate	0.84%	0.84%
Average receive rate	5.53%	4.75%
Average maturity (Year)	3 years 2 months 12 days	3 years 8 months 12 days
More Than Five Years [Member]
Notional amount	$ 1,651.5	$ 900.0
Average fixed pay rate	2.53%	1.70%
Average receive rate	5.14%	4.23%
Average maturity (Year)	6 years 10 months 24 days	6 years 7 months 6 days