The useful life of the loan receivable.

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The period of time when the final, large payment is due on a real estate loan.

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The ratio used to analyze the amount of debt that can be supported by the cash flow generated from the property. The calculation is the net income generated by the property divided by the commercial mortgage payment.

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The amount of the mortgage loan as a percentage of the total appraised value of the real property. Loan-to-value is one of the key risk factors that lenders assess when qualifying borrowers for a mortgage.

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Specifies the time period covered by the loan receivable.

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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 held-for-sale and loans and leases covered under loss sharing agreements.

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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.

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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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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.

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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.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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The face amount of loans that will be sold to other entities.

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Amount, after allowance for bad debt, of loan receivables held-for-sale that are not part of a disposal group. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes loans held for sale. Excludes loans and leases covered under loss sharing agreements.

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Amount of deferred fees paid by borrowers and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield. Excludes amounts for loans and leases covered under loss sharing agreements.

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Loans and Allowance for Loan Losses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	$ 2,658,136	$ 1,946,114
Loans Receivable Held-for-sale, Amount	1,508	1,025
loans and leases receivable gross excluding loans held for sale	2,656,628	1,945,089
Net deferred loan fees, premiums and discounts	(13,617)	(6,613)
Allowance for loan losses	26,189	19,977	$ 16,753	$ 14,576
Net loans	2,616,822	1,918,499
Loans held for sale	1,508	1,025
Increase (Decrease) in Accounts and Notes Receivable	698,300
Loans Receivable, Net	2,644,519	1,939,501
Construction and land development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	51,013	107,721
Loans Receivable, Net	50,619	107,594
Farm loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	232,409	127,232
Loans Receivable, Net	231,700	127,183
1-4 Family residential properties
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	374,751	294,483
Loans Receivable, Net	373,518	293,667
Multifamily residential properties
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	186,393	61,966
Loans Receivable, Net	184,051	61,798
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	911,656	684,639
Loans Receivable, Net	$ 906,850	681,757
Debt coverage ratio	1.20x
Amortization period of loans	twenty years
Commercial real estate \| Minimum [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan To Value Ratio	65.00%
Commercial real estate \| Maximum [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan To Value Ratio	80.00%
Loans secured by real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	$ 1,756,222	1,276,041
Loans Receivable, Net	1,746,738	1,271,999
Agricultural loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	136,125	86,602
Loans Receivable, Net	135,877	86,631
Commercial and industrial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	559,120	445,378
Loans Receivable, Net	$ 557,011	444,263
Loan To Value Ratio	80.00%
Amortization period of loans	seven years
Loans Receivable, Time Period	one year
Consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	$ 92,744	30,070
Allowance for loan losses	932	803	693	642
Loans Receivable, Net	91,516	29,749
All other loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	113,925	108,023
Loans Receivable, Net	113,377	106,859
Agricultural and Farm Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	368,534	213,834
Increase (Decrease) in Accounts and Notes Receivable	$ 154,700
Loan To Value Ratio	65.00%
Amortization period of loans	twenty five years
Loans Receivable, Time Period	one year
Other Grain Farming [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	$ 276,100	170,758
Increase (Decrease) in Accounts and Notes Receivable	105,300
Motels and Hotels Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	129,216	131,702
Non-residential Buildings [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	250,495	185,967
Residential Buildings [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	289,169	131,756
Other Gambling Industries [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	105,259	95,713
Commercial/Commercial Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	21,556	16,546	12,901	11,379
Agriculture/Agricultural Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	2,197	1,742	2,249	1,337
Residential Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	$ 1,504	886	874	994
Loan To Value Ratio	80.00%
Amortization period of loans	twenty five years
Balloon period	five years
Unallocated [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	$ 0	$ 0	$ 36	$ 224