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Loans Held for Sale - Narrative (Details) - USD ($)		3 Months Ended			9 Months Ended
Loans Held for Sale - Narrative (Details) - USD ($)	Feb. 01, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Mortgage loans held for sale		$ 93,600,000			$ 93,600,000		$ 30,100,000
Nonaccrual loans		43,100,000			43,100,000
Loans held for sale considered a troubled debt restructuring					0
Transfer of loans to held-for-sale					12,400,000	$ 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
Goodwill, Period Increase (Decrease)		200,000
Proceeds from Collection of Loans Held-for-sale			$ 108,700,000
Loans held for sale
Debt Securities, Available-for-sale [Line Items]
Goodwill, Period Increase (Decrease)			35,100,000
Commercial
Debt Securities, Available-for-sale [Line Items]
Nonaccrual loans		11,700,000			11,700,000		5,000,000.0
Proceeds from Sale of Loans Held-for-sale		12,400,000	$ 23,400,000
Agricultural
Debt Securities, Available-for-sale [Line Items]
Transfer of loans from held-for-sale to held for investment				19,800,000
Cost basis after charge-off				$ 14,700,000
Residential
Debt Securities, Available-for-sale [Line Items]
Mortgage loans held for sale		18,200,000			18,200,000		30,100,000
Agricultural
Debt Securities, Available-for-sale [Line Items]
Mortgage loans held for sale		63,000,000.0			63,000,000.0		0
Nonaccrual loans		30,700,000			30,700,000
Transfer of loans to held-for-sale	$ 155,800,000
Commercial construction
Debt Securities, Available-for-sale [Line Items]
Transfer of loans to held-for-sale	$ 24,000,000
Commercial construction
Debt Securities, Available-for-sale [Line Items]
Mortgage loans held for sale		12,400,000			12,400,000		$ 0
Nonaccrual loans		$ 12,400,000			$ 12,400,000