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Loans Held for Sale - Narrative (Details) - USD ($)		3 Months Ended
Loans Held for Sale - Narrative (Details) - USD ($)	Feb. 01, 2022	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Mortgage loans held for sale		$ 178,100,000		$ 30,100,000
Loans held for sale considered a troubled debt restructuring		0
Transfer of loans from held-for-sale to held for investment		19,800,000	$ 0
Allowance for loan losses, charge-off		5,100,000
Agricultural
Debt Securities, Available-for-sale [Line Items]
Mortgage loans held for sale		132,100,000		0
Nonaccrual loans		32,700,000
Transfer of loans to held-for-sale	$ 155,800,000
Transfer of loans from held-for-sale to held for investment		19,800,000
Cost basis after charge-off		14,700,000
Commercial
Debt Securities, Available-for-sale [Line Items]
Mortgage loans held for sale		23,400,000		0
Transfer of loans to held-for-sale	$ 24,000,000
Residential
Debt Securities, Available-for-sale [Line Items]
Mortgage loans held for sale		$ 22,600,000		$ 30,100,000