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Allowance for Probable Loan Losses (By Loan Class) (Details) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2016 USD ($) | Mar. 31, 2016 USD ($) | Dec. 31, 2016 USD ($) item | Dec. 31, 2015 USD ($) | Dec. 31, 2014 USD ($)
Allowance for probable loan losses |  |  |  |  |
Balance at the beginning of the period |  | $ 66,988 | $ 66,988 | $ 64,828 | $ 70,161
Losses charged to allowance |  |  | (35,901) | (27,125) | (23,465)
Recoveries credited to allowance |  |  | 13,715 | 4,880 | 3,709
Net (losses) recoveries charged to allowance |  |  | (22,186) | (22,245) | (19,756)
Provision charged to operations |  |  | 19,859 | 24,405 | 14,423
Balance at the end of the period |  |  | $ 64,661 | 66,988 | 64,828
Number of large recoveries | item |  |  | 2 |  |
Watch - List Impaired |  |  |  |  |
Allowance for probable loan losses |  |  |  |  |
Losses charged to allowance |  |  | $ (19,400) |  |
Commercial |  |  |  |  |
Allowance for probable loan losses |  |  |  |  |
Balance at the beginning of the period |  | 21,431 | 21,431 | 22,352 | 22,433
Losses charged to allowance |  |  | (32,959) | (24,802) | (19,110)
Recoveries credited to allowance |  | 4,400 | 7,110 | 3,135 | 2,979
Net (losses) recoveries charged to allowance |  |  | (25,849) | (21,667) | (16,131)
Provision charged to operations |  |  | 30,067 | 20,746 | 16,050
Balance at the end of the period |  |  | 25,649 | 21,431 | 22,352
Commercial | Transportation Equipment |  |  |  |  |
Allowance for probable loan losses |  |  |  |  |
Losses charged to allowance |  |  |  | (13,500) | (8,500)
Commercial Real Estate: Other Construction and Land Development |  |  |  |  |
Allowance for probable loan losses |  |  |  |  |
Balance at the beginning of the period |  | 13,920 | 13,920 | 12,955 | 12,541
Losses charged to allowance |  |  | (16) | (695) | (680)
Recoveries credited to allowance | $ 6,000 |  | 6,099 | 141 | 72
Net (losses) recoveries charged to allowance |  |  | 6,083 | (554) | (608)
Provision charged to operations |  |  | (6,114) | 1,519 | 1,022
Balance at the end of the period |  |  | 13,889 | 13,920 | 12,955
Commercial Real Estate: Farmland & Commercial |  |  |  |  |
Allowance for probable loan losses |  |  |  |  |
Balance at the beginning of the period |  | 19,769 | 19,769 | 18,683 | 24,467
Losses charged to allowance |  |  | (1,890) | (492) | (1,893)
Recoveries credited to allowance |  |  | 119 | 963 | 107
Net (losses) recoveries charged to allowance |  |  | (1,771) | 471 | (1,786)
Provision charged to operations |  |  | (1,267) | 615 | (3,998)
Balance at the end of the period |  |  | 16,731 | 19,769 | 18,683
Commercial Real Estate: Multifamily |  |  |  |  |
Allowance for probable loan losses |  |  |  |  |
Balance at the beginning of the period |  | 1,248 | 1,248 | 846 | 776
Losses charged to allowance |  |  | (180) |  |
Net (losses) recoveries charged to allowance |  |  | (180) |  |
Provision charged to operations |  |  | (262) | 402 | 70
Balance at the end of the period |  |  | 806 | 1,248 | 846
Residential First Lien |  |  |  |  |
Allowance for probable loan losses |  |  |  |  |
Balance at the beginning of the period |  | 3,509 | 3,509 | 3,589 | 3,812
Losses charged to allowance |  |  | (70) | (157) | (351)
Recoveries credited to allowance |  |  | 21 | 30 | 49
Net (losses) recoveries charged to allowance |  |  | (49) | (127) | (302)
Provision charged to operations |  |  | (1,005) | 47 | 79
Balance at the end of the period |  |  | 2,455 | 3,509 | 3,589
Residential Junior Lien |  |  |  |  |
Allowance for probable loan losses |  |  |  |  |
Balance at the beginning of the period |  | 5,321 | 5,321 | 4,683 | 4,249
Losses charged to allowance |  |  | (331) | (275) | (661)
Recoveries credited to allowance |  |  | 278 | 431 | 242
Net (losses) recoveries charged to allowance |  |  | (53) | 156 | (419)
Provision charged to operations |  |  | (1,552) | 482 | 853
Balance at the end of the period |  |  | 3,716 | 5,321 | 4,683
Consumer |  |  |  |  |
Allowance for probable loan losses |  |  |  |  |
Balance at the beginning of the period |  | 638 | 638 | 660 | 750
Losses charged to allowance |  |  | (414) | (704) | (719)
Recoveries credited to allowance |  |  | 69 | 170 | 210
Net (losses) recoveries charged to allowance |  |  | (345) | (534) | (509)
Provision charged to operations |  |  | 238 | 512 | 419
Balance at the end of the period |  |  | 531 | 638 | 660
Foreign |  |  |  |  |
Allowance for probable loan losses |  |  |  |  |
Balance at the beginning of the period |  | $ 1,152 | 1,152 | 1,060 | 1,133
Losses charged to allowance |  |  | (41) |  | (51)
Recoveries credited to allowance |  |  | 19 | 10 | 50
Net (losses) recoveries charged to allowance |  |  | (22) | 10 | (1)
Provision charged to operations |  |  | (246) | 82 | (72)
Balance at the end of the period |  |  | $ 884 | $ 1,152 | $ 1,060

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- Definition Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(4) -URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524 + Details
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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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.7(d)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section S99 -Paragraph 4 -Subparagraph (SAB Topic 6.L.1) -URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74567-122707 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (b)(1)(ii) -URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544 + Details
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