Loans - Amounts of Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan Balance	$ 3,707,299	$ 3,634,596
Total loans		3,636,841
Allowance for loan losses	(48,440)	(17,667)
Loans, net	3,658,859	3,619,174
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial/Consumer, Total		2,046,651
Loan Balance	2,050,402	2,047,646
Real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Real Estate, Total		770,717
Loan Balance	981,048	920,998
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial/Consumer, Total		669,180
Loan Balance	675,849	665,952
Working capital and equipment \| Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial/Consumer, Total		938,317
Real estate, including agriculture \| Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial/Consumer, Total		978,891
Tax exempt \| Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial/Consumer, Total		63,571
Other \| Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial/Consumer, Total		65,872
1-4 family \| Real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Real Estate, Total		762,571
Other \| Real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Real Estate, Total		8,146
Auto \| Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial/Consumer, Total		362,729
Recreation \| Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial/Consumer, Total		16,262
Real estate/home improvement \| Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial/Consumer, Total		43,585
Home equity \| Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial/Consumer, Total		237,979
Loan Balance	$ 275,492	276,215
Unsecured \| Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial/Consumer, Total		7,286
Other \| Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial/Consumer, Total		1,339
Mortgage warehouse
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan Balance		$ 150,293

Loans net of allowance for loan losses.

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- Definition

Loans receivable real estate.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount, before allowance and fees, of loans and leases receivable. Excludes loans and leases covered under loss sharing agreements.

+ References

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-Publisher FASB
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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

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- Definition

Amount, before allowance for credit loss, of financing receivable.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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