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The increase (decrease) during the reporting period of the sum of amounts due within one year (or one business cycle) from customers for the credit sale of goods and services; and from note holders for outstanding loans.

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Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period).

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Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

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Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

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Loans and Allowance for Credit Losses - Additional Information (Details)	12 Months Ended
	Dec. 31, 2021 USD ($) alternative Loan_modified	Dec. 31, 2020 USD ($) Loan_modified	Dec. 31, 2019 USD ($)	Jan. 01, 2020 USD ($)	Dec. 31, 2018 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Increase (decrease) in accounts and notes receivable	$ 844,000
Loan purchased amount	3,938,120,000	$ 3,094,585,000
Accrued interest on loans	14,700,000	15,900,000
Minimum value of loans individually measured for impairment	$ 250,000,000
Number of alternatives for measuring impaired loans receivable \| alternative	3
Allowance for credit losses	$ 54,655,000	41,910,000	$ 26,911,000		$ 26,189,000
Recorded balance of nonaccrual loans	18,105,000	23,750,000
Interest lost on nonaccrual loans	308,000	921,000	906,000
Troubled debt restructurings balance	5,792,000	9,502,000
Loans receivable, modifications, allowance	$ 765,000	$ 1,016,000
Troubled debt restructurings balance \| Loan_modified	1	0
Real estate acquired through foreclosure	$ 4,984,000	$ 2,489,000
Mortgage loans secured by real estate In foreclosure	$ 411,000	713,000
ASU 2016-13
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses				$ 28,583,000
ASU 2016-13 \| Revision of Prior Period, Adjustment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses				1,672,000
ASU 2016-13 \| Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses				1,198,000
ASU 2016-13 \| Financial Asset Acquired with Credit Deterioration \| Revision of Prior Period, Adjustment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses				833,000
Commercial and Industrial Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Maximum loan-to-value ratio (in hundredths)	80.00%
Amortization period of loans	seven years
Loans receivable, time period	one year
Allowance for credit losses	$ 19,241,000	13,485,000	9,273,000		9,893,000
Troubled debt restructurings balance	$ 479,000	2,389,000
Agricultural
Accounts, Notes, Loans and Financing Receivable [Line Items]
Maximum loan-to-value ratio (in hundredths)	65.00%
Amortization period of loans	twenty-five years
Loans receivable, time period	one year
Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Debt coverage ratio	1.20x
Amortization period of loans	twenty years
Recorded balance of nonaccrual loans	$ 7,920,000	8,760,000
Commercial Real Estate \| ASU 2016-13
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses				11,739,000
Commercial Real Estate \| ASU 2016-13 \| Revision of Prior Period, Adjustment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses				541,000
Commercial Real Estate \| ASU 2016-13 \| Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses				818,000
Commercial Real Estate \| ASU 2016-13 \| Financial Asset Acquired with Credit Deterioration \| Revision of Prior Period, Adjustment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses				459,000
Commercial Real Estate \| Minimum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Maximum loan-to-value ratio (in hundredths)	65.00%
Commercial Real Estate \| Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Maximum loan-to-value ratio (in hundredths)	80.00%
1-4 Family Residential Properties
Accounts, Notes, Loans and Financing Receivable [Line Items]
Period when loans charged-down	180 days
Recorded balance of nonaccrual loans	$ 5,252,000	6,930,000
1-4 Family Residential Properties \| ASU 2016-13
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses				2,142,000
1-4 Family Residential Properties \| ASU 2016-13 \| Revision of Prior Period, Adjustment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses				756,000
1-4 Family Residential Properties \| ASU 2016-13 \| Financial Asset Acquired with Credit Deterioration
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses				48,000
1-4 Family Residential Properties \| ASU 2016-13 \| Financial Asset Acquired with Credit Deterioration \| Revision of Prior Period, Adjustment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses				$ 42,000
Providence Bank
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan purchased amount	838,400,000
Stifel Bank
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan purchased amount	208,000,000
Real Estate Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled debt restructurings balance	4,953,000	6,773,000
Real Estate Loan \| Agricultural
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses	$ 1,257,000	$ 1,084,000	$ 1,093,000		$ 1,246,000
Real Estate Loan \| Residential Properties
Accounts, Notes, Loans and Financing Receivable [Line Items]
Maximum loan-to-value ratio (in hundredths)	80.00%
Amortization period of loans	twenty-five years
Balloon period	five years
Unsecured Open-end Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Period when loans charged-down	180 days
Other Secured Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Period when loans charged-down	120 days