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Loans - Schedule of Loans by Class (Details) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2017 | Dec. 31, 2016
Loans and Leases Receivable |  |
Loans held for investment | $ 7,567,720 | $ 5,416,750
Mortgage loans held for sale | 46,635 | 61,794
Total loans | 7,614,355 | 5,478,544
Commercial |  |
Loans and Leases Receivable |  |
Loans held for investment | $ 2,822,900 | 1,834,400
Loans receivable, maturity | 5 years |
Land acquisition & development |  |
Loans and Leases Receivable |  |
Loans held for investment | $ 348,700 | 208,500
Residential |  |
Loans and Leases Receivable |  |
Loans held for investment | 240,200 | 147,900
Commercial |  |
Loans and Leases Receivable |  |
Loans held for investment | 119,400 | 125,600
Total construction loans |  |
Loans and Leases Receivable |  |
Loans held for investment | 708,300 | 482,000
Residential |  |
Loans and Leases Receivable |  |
Loans held for investment | $ 1,487,400 | 1,027,400
Loans receivable, maturity | 15 years |
Agricultural |  |
Loans and Leases Receivable |  |
Loans held for investment | $ 158,200 | 170,200
Total real estate loans |  |
Loans and Leases Receivable |  |
Loans held for investment | 5,176,800 | 3,514,000
Indirect consumer |  |
Loans and Leases Receivable |  |
Loans held for investment | 784,700 | 752,400
Other consumer |  |
Loans and Leases Receivable |  |
Loans held for investment | 175,100 | 148,100
Credit card consumer |  |
Loans and Leases Receivable |  |
Loans held for investment | 74,600 | 69,800
Total consumer loans |  |
Loans and Leases Receivable |  |
Loans held for investment | 1,034,400 | 970,300
Commercial |  |
Loans and Leases Receivable |  |
Loans held for investment | 1,215,400 | 797,900
Agricultural |  |
Loans and Leases Receivable |  |
Loans held for investment | 136,200 | 132,900
Other, including overdrafts |  |
Loans and Leases Receivable |  |
Loans held for investment | 4,900 | 1,600
Loans held for investment |  |
Loans and Leases Receivable |  |
Loans held for investment | 7,567,700 | 5,416,700
Total loans |  |
Loans and Leases Receivable |  |
Total loans | 7,614,300 | 5,478,500
Home equity line of credit |  |
Loans and Leases Receivable |  |
Loans held for investment | $ 397,000 | $ 321,500
Loans receivable, loan to value limit | 80.00% |

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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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522 + Details
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- Definition Amount, after allowance for bad debt, of mortgage 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522 + Details
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