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Allowance for Probable Loan Losses (Portfolio Credit Quality By Loan Class) (Details) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2017 USD ($) item | Dec. 31, 2016 USD ($)
Loan portfolio by credit quality indicator |  |
Portfolio, total | $ 6,348,172 | $ 5,964,688
Number of additional relationships reclassified from Pass to Watch List - Substandard | item | 3 |
Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | $ 5,911,001 | 5,544,614
Special Review |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 6,612 | 101,679
Watch List - Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 45,662 | 60,993
Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 321,693 | 208,997
Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 63,204 | 48,405
Commercial |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,086,467 | 909,667
Commercial | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 905,707 | 720,350
Commercial | Special Review |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total |  | 90,746
Commercial | Watch List - Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 3,170 | 1,121
Commercial | Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 159,643 | 75,038
Commercial | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 17,947 | 22,412
Commercial Real Estate: Other Construction and Land Development |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,683,550 | 1,716,875
Commercial Real Estate: Other Construction and Land Development | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,616,604 | 1,648,633
Commercial Real Estate: Other Construction and Land Development | Special Review |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,288 | 1,986
Commercial Real Estate: Other Construction and Land Development | Watch List - Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 672 |
Commercial Real Estate: Other Construction and Land Development | Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 62,531 | 61,480
Commercial Real Estate: Other Construction and Land Development | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 2,455 | 4,776
Commercial Real Estate: Farmland & Commercial |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 2,043,285 | 1,943,070
Commercial Real Estate: Farmland & Commercial | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,863,763 | 1,792,542
Commercial Real Estate: Farmland & Commercial | Special Review |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 5,134 | 7,983
Commercial Real Estate: Farmland & Commercial | Watch List - Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 41,820 | 59,872
Commercial Real Estate: Farmland & Commercial | Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 99,445 | 71,863
Commercial Real Estate: Farmland & Commercial | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 33,123 | 10,810
Commercial Real Estate: Multifamily |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 192,916 | 140,466
Commercial Real Estate: Multifamily | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 192,440 | 139,914
Commercial Real Estate: Multifamily | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 476 | 552
Residential First Lien |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 432,777 | 421,904
Residential First Lien | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 425,811 | 413,638
Residential First Lien | Special Review |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 40 | 814
Residential First Lien | Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 74 | 616
Residential First Lien | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 6,852 | 6,836
Residential Junior Lien |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 700,748 | 610,318
Residential Junior Lien | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 699,875 | 609,190
Residential Junior Lien | Special Review |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 150 | 150
Residential Junior Lien | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 723 | 978
Consumer |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 49,543 | 55,168
Consumer | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 48,262 | 53,873
Consumer | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,281 | 1,295
Foreign |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 158,886 | 167,220
Foreign | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 158,539 | 166,474
Foreign | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | $ 347 | $ 746

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- Definition Amount before allowance and after 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. + 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 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5074-111524 + Details
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