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Allowance for Probable Loan Losses (By Loan Class) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017
Allowance for probable loan losses |  |  |  |
Balance at the beginning of the period | $ 67,154 | $ 64,186 | $ 67,687 | $ 64,661
Losses charged to allowance | (2,458) | (2,406) | (5,335) | (5,398)
Recoveries credited to allowance | 887 | 2,334 | 1,569 | 3,151
Net (losses) recoveries charged to allowance | (1,571) | (72) | (3,766) | (2,247)
Provision charged to operations | (2,730) | 805 | (1,068) | 2,505
Balance at the end of the period | 62,853 | 64,919 | $ 62,853 | 64,919
Period of time for determining the historical charge-off experience |  |  | 3 years |
Commercial |  |  |  |
Allowance for probable loan losses |  |  |  |
Balance at the beginning of the period | 20,691 | 25,853 | $ 27,905 | 25,649
Losses charged to allowance | (2,284) | (2,264) | (4,999) | (4,999)
Recoveries credited to allowance | 447 | 2,154 | 1,030 | 2,853
Net (losses) recoveries charged to allowance | (1,837) | (110) | (3,969) | (2,146)
Provision charged to operations | (2,258) | (603) | (7,340) | 1,637
Balance at the end of the period | 16,596 | 25,140 | 16,596 | 25,140
Commercial Real Estate:Other Construction and Land Development |  |  |  |
Allowance for probable loan losses |  |  |  |
Balance at the beginning of the period | 11,798 | 13,789 | 11,675 | 13,889
Losses charged to allowance |  |  | (1) |
Recoveries credited to allowance | 2 | 2 | 4 | 3
Net (losses) recoveries charged to allowance | 2 | 2 | 3 | 3
Provision charged to operations | 2,903 | (542) | 3,025 | (643)
Balance at the end of the period | 14,703 | 13,249 | 14,703 | 13,249
Commercial Real Estate: Farmland and Commercial |  |  |  |
Allowance for probable loan losses |  |  |  |
Balance at the beginning of the period | 24,803 | 16,721 | 16,663 | 16,731
Losses charged to allowance | (70) | (40) | (70) | (40)
Recoveries credited to allowance | 192 | 89 | 210 | 147
Net (losses) recoveries charged to allowance | 122 | 49 | 140 | 107
Provision charged to operations | (6,629) | 702 | 1,493 | 634
Balance at the end of the period | 18,296 | 17,472 | 18,296 | 17,472
Commercial Real Estate: Multifamily |  |  |  |
Allowance for probable loan losses |  |  |  |
Balance at the beginning of the period | 947 | 818 | 1,109 | 806
Provision charged to operations | 627 | 179 | 465 | 191
Balance at the end of the period | 1,574 | 997 | 1,574 | 997
Residential First Lien |  |  |  |
Allowance for probable loan losses |  |  |  |
Balance at the beginning of the period | 3,006 | 2,391 | 2,950 | 2,455
Losses charged to allowance | (30) | (30) | (44) | (61)
Recoveries credited to allowance | 1 | 2 | 2 | 7
Net (losses) recoveries charged to allowance | (29) | (28) | (42) | (54)
Provision charged to operations | 614 | (49) | 683 | (87)
Balance at the end of the period | 3,591 | 2,314 | 3,591 | 2,314
Residential Junior Lien |  |  |  |
Allowance for probable loan losses |  |  |  |
Balance at the beginning of the period | 4,689 | 3,186 | 6,103 | 3,716
Losses charged to allowance | (9) | (33) | (39) | (138)
Recoveries credited to allowance | 229 | 73 | 295 | 97
Net (losses) recoveries charged to allowance | 220 | 40 | 256 | (41)
Provision charged to operations | 1,884 | 1,131 | 434 | 682
Balance at the end of the period | 6,793 | 4,357 | 6,793 | 4,357
Consumer |  |  |  |
Allowance for probable loan losses |  |  |  |
Balance at the beginning of the period | 437 | 504 | 440 | 531
Losses charged to allowance | (65) | (39) | (182) | (160)
Recoveries credited to allowance | 15 | 13 | 27 | 29
Net (losses) recoveries charged to allowance | (50) | (26) | (155) | (131)
Provision charged to operations | 63 | 10 | 165 | 88
Balance at the end of the period | 450 | 488 | 450 | 488
Foreign |  |  |  |
Allowance for probable loan losses |  |  |  |
Balance at the beginning of the period | 783 | 924 | 842 | 884
Recoveries credited to allowance | 1 | 1 | 1 | 15
Net (losses) recoveries charged to allowance | 1 | 1 | 1 | 15
Provision charged to operations | 66 | (23) | 7 | 3
Balance at the end of the period | $ 850 | $ 902 | $ 850 | $ 902

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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=84173941&loc=SL6953423-111524 + Details
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- Definition Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss. + 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)(3) -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524 Reference 2: 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 + 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=84173941&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=84173941&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=82894903&loc=d3e15032-111544 + Details
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