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Loans Held for Sale - By Segment (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Debt Securities, Available-for-sale [Line Items]
Loans held for sale ($0.6 and $0.9 of which is recorded at fair value at September 30, 2025 and December 31, 2024, respectively)	$ 305.6	$ 0.9
Agricultural
Debt Securities, Available-for-sale [Line Items]
Loans held for sale ($0.6 and $0.9 of which is recorded at fair value at September 30, 2025 and December 31, 2024, respectively)	5.1	0.0
Commercial
Debt Securities, Available-for-sale [Line Items]
Loans held for sale ($0.6 and $0.9 of which is recorded at fair value at September 30, 2025 and December 31, 2024, respectively)	214.6	0.0
Total construction loans
Debt Securities, Available-for-sale [Line Items]
Loans held for sale ($0.6 and $0.9 of which is recorded at fair value at September 30, 2025 and December 31, 2024, respectively)	0.2	0.0
Residential Mortgage
Debt Securities, Available-for-sale [Line Items]
Loans held for sale ($0.6 and $0.9 of which is recorded at fair value at September 30, 2025 and December 31, 2024, respectively)	0.7	0.0
Agricultural
Debt Securities, Available-for-sale [Line Items]
Loans held for sale ($0.6 and $0.9 of which is recorded at fair value at September 30, 2025 and December 31, 2024, respectively)	15.4	0.0
Total real estate
Debt Securities, Available-for-sale [Line Items]
Loans held for sale ($0.6 and $0.9 of which is recorded at fair value at September 30, 2025 and December 31, 2024, respectively)	231.5	0.9
Consumer Loan
Debt Securities, Available-for-sale [Line Items]
Loans held for sale ($0.6 and $0.9 of which is recorded at fair value at September 30, 2025 and December 31, 2024, respectively)	0.8	0.0
Total consumer loans
Debt Securities, Available-for-sale [Line Items]
Loans held for sale ($0.6 and $0.9 of which is recorded at fair value at September 30, 2025 and December 31, 2024, respectively)	0.8	0.0
Commercial
Debt Securities, Available-for-sale [Line Items]
Loans held for sale ($0.6 and $0.9 of which is recorded at fair value at September 30, 2025 and December 31, 2024, respectively)	68.2	0.0
Residential Mortgage, at fair value
Debt Securities, Available-for-sale [Line Items]
Loans held for sale ($0.6 and $0.9 of which is recorded at fair value at September 30, 2025 and December 31, 2024, respectively)	$ 0.6	$ 0.9

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- Definition

Fair value portion of mortgage loans held-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
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