Allowance for Loan and Lease Losses - Activity in Allowance for Loan and Lease Losses (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually	$ 15,787	$ 16,072
Collectively	1,781,873	1,715,856
Total Financing Receivables	1,797,660	1,731,928
Real Estate Sector [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually	14,265	13,501
Collectively	1,393,489	1,440,429
Total Financing Receivables	1,407,754	1,453,930
Agricultural Sector [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually	6	6
Collectively	49,099	49,097
Total Financing Receivables	49,105	49,103
Commercial and Industrial and Mortgage Warehouse Sector [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually	810	1,744
Collectively	331,840	218,289
Total Financing Receivables	332,650	220,033
Consumer Loans Sector [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually	706	821
Collectively	7,445	8,041
Total Financing Receivables	$ 8,151	$ 8,862

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- Definition

The balance of financing receivables that were collectively evaluated for impairment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524

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- Definition

The balance of financing receivables that were individually evaluated for impairment.

+ References

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- Definition

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=118952595&loc=d3e4428-111522

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