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Loans Held for Sale - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Schedule of Available-for-sale Securities
Loans Held for Sale	$ 73.6	$ 0.9
Amortization of unrealized gains and losses on transfers of securities	370.0	0.0	$ 30.4
Transfer of Loans Held-for-sale to Portfolio Loans	0.0	0.0	(29.6)
Transfer of loans to other real estate owned	0.5	4.6	$ 8.3
Financing Receivables, Equal to Greater than 90 Days Past Due
Schedule of Available-for-sale Securities
Non-accrual Loans	60.5	40.5
Commercial Portfolio Segment [Member]
Schedule of Available-for-sale Securities
Non-accrual Loans	21.7	33.5
Agricultural Financing Receivable [Member]
Schedule of Available-for-sale Securities
Non-accrual Loans	24.6	20.9
Agricultural Financing Receivable [Member]
Schedule of Available-for-sale Securities
Loans Held for Sale	20.5	0.0
Residential Real Estate
Schedule of Available-for-sale Securities
Loans Held for Sale	1.1	0.9
Commercial Real Estate Portfolio Segment [Member]
Schedule of Available-for-sale Securities
Loans Held for Sale	19.5	0.0
Real Estate Construction Financing Receivable [Member]
Schedule of Available-for-sale Securities
Loans Held for Sale	1.3	0.0
Residential Mortgage [Member]
Schedule of Available-for-sale Securities
Loans Held for Sale	3.5	0.0
Residential Mortgage, at fair value
Schedule of Available-for-sale Securities
Loans Held for Sale	1.1	0.9
Agricultural Real Estate Financing Receivable [Member]
Schedule of Available-for-sale Securities
Loans Held for Sale	17.8	0.0
Real Estate Financing Receivable [Member]
Schedule of Available-for-sale Securities
Loans Held for Sale	43.2	0.9
Other consumer
Schedule of Available-for-sale Securities
Loans Held for Sale	2.5	0.0
Total consumer loans
Schedule of Available-for-sale Securities
Loans Held for Sale	2.5	0.0
Commercial Portfolio Segment [Member]
Schedule of Available-for-sale Securities
Loans Held for Sale	$ 7.4	$ 0.0