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Capital Requirements (Capital Amounts and Ratios) (Details) - USD ($) $ in Thousands | Dec. 31, 2021 | Dec. 31, 2020
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Parent Company |  |
Capital Requirements |  |
Common Equity Tier 1 Capital (to Risk Weighted Assets), Actual Amount | $ 2,057,928 | $ 1,874,641
Common Equity Tier 1 Capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 20.47% | 19.05%
Total Capital (to Risk Weighted Assets), Actual Amount | $ 2,284,579 | $ 2,105,360
Total Capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 22.73 | 21.40
Tier 1 Capital (to Risk Weighted Assets), Actual Amount | $ 2,170,682 | $ 1,992,403
Tier 1 capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 21.59 | 20.25
Tier 1 Capital (to Average Assets), Actual Amount | $ 2,170,682 | $ 1,992,403
Tier 1 capital (to Average Assets), Actual Ratio (as a percent) | 13.94 | 14.92
Parent Company | Minimum |  |
Capital Requirements |  |
Common Equity Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 703,710 | $ 688,678
Common Equity Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 7.00% | 7.00%
Total Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 1,055,565 | $ 1,033,017
Total Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 10.500 | 10.500
Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 854,505 | $ 836,252
Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 8.500 | 8.500
Tier 1 Capital (to Average Assets), For Capital Adequacy Purposes Amount | $ 622,671 | $ 534,228
Tier 1 Capital (to Average Assets), For Capital Adequacy Purposes Ratio (as a percent) | 4.00 | 4.00
International Bank of Commerce Laredo |  |
Capital Requirements |  |
Common Equity Tier 1 Capital (to Risk Weighted Assets), Actual Amount | $ 1,287,687 | $ 1,295,437
Common Equity Tier 1 Capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 19.74% | 18.19%
Total Capital (to Risk Weighted Assets), Actual Amount | $ 1,367,487 | $ 1,380,685
Total Capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 20.97 | 19.39
Tier 1 Capital (to Risk Weighted Assets), Actual Amount | $ 1,287,687 | $ 1,295,437
Tier 1 capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 19.74 | 18.19
Tier 1 Capital (to Average Assets), Actual Amount | $ 1,287,687 | $ 1,295,437
Tier 1 capital (to Average Assets), Actual Ratio (as a percent) | 11.14 | 13.11
International Bank of Commerce Laredo | Minimum |  |
Capital Requirements |  |
Common Equity Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 456,544 | $ 498,492
Common Equity Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 423,934 | $ 462,885
Common Equity Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 7.00% | 7.00%
Common Equity Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 6.50% | 6.50%
Total Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 684,816 | $ 747,737
Total Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 652,206 | $ 712,131
Total Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 10.500 | 10.500
Total Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 10.00 | 10.00
Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 554,375 | $ 605,311
Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 521,764 | $ 569,705
Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 8.500 | 8.500
Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 8.00 | 8.00
Tier 1 Capital (to Average Assets), For Capital Adequacy Purposes Amount | $ 462,225 | $ 395,289
Tier 1 Capital (to Average Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 577,781 | $ 494,112
Tier 1 Capital (to Average Assets), For Capital Adequacy Purposes Ratio (as a percent) | 4.00 | 4.00
Tier 1 Capital (to Average Assets), To Be well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 5.00 | 5.00
International Bank of Commerce Brownsville |  |
Capital Requirements |  |
Common Equity Tier 1 Capital (to Risk Weighted Assets), Actual Amount | $ 315,957 | $ 189,575
Common Equity Tier 1 Capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 19.80% | 22.18%
Total Capital (to Risk Weighted Assets), Actual Amount | $ 334,495 | $ 200,269
Total Capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 20.96 | 23.43
Tier 1 Capital (to Risk Weighted Assets), Actual Amount | $ 315,957 | $ 189,575
Tier 1 capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 19.80 | 22.18
Tier 1 Capital (to Average Assets), Actual Amount | $ 315,957 | $ 189,575
Tier 1 capital (to Average Assets), Actual Ratio (as a percent) | 20.17 | 14.55
International Bank of Commerce Brownsville | Minimum |  |
Capital Requirements |  |
Common Equity Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 111,690 | $ 59,843
Common Equity Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 103,712 | $ 55,569
Common Equity Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 7.00% | 7.00%
Common Equity Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 6.50% | 6.50%
Total Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 167,535 | $ 89,765
Total Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 159,557 | $ 85,490
Total Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 10.500 | 10.500
Total Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 10.00 | 10.00
Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 135,623 | $ 72,667
Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 127,645 | $ 68,392
Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 8.500 | 8.500
Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 8.00 | 8.00
Tier 1 Capital (to Average Assets), For Capital Adequacy Purposes Amount | $ 62,663 | $ 52,101
Tier 1 Capital (to Average Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 78,329 | $ 65,127
Tier 1 Capital (to Average Assets), For Capital Adequacy Purposes Ratio (as a percent) | 4.00 | 4.00
Tier 1 Capital (to Average Assets), To Be well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 5.00 | 5.00
International Bank Of Commerce Oklahoma |  |
Capital Requirements |  |
Common Equity Tier 1 Capital (to Risk Weighted Assets), Actual Amount | $ 221,567 | $ 207,339
Common Equity Tier 1 Capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 18.59% | 17.45%
Total Capital (to Risk Weighted Assets), Actual Amount | $ 232,454 | $ 218,657
Total Capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 19.50 | 18.41
Tier 1 Capital (to Risk Weighted Assets), Actual Amount | $ 221,567 | $ 207,339
Tier 1 capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 18.59 | 17.45
Tier 1 Capital (to Average Assets), Actual Amount | $ 221,567 | $ 207,339
Tier 1 capital (to Average Assets), Actual Ratio (as a percent) | 11.49 | 12.98
International Bank Of Commerce Oklahoma | Minimum |  |
Capital Requirements |  |
Common Equity Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 83,452 | $ 83,150
Common Equity Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 77,491 | $ 77,211
Common Equity Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 7.00% | 7.00%
Common Equity Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 6.50% | 6.50%
Total Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 125,178 | $ 124,725
Total Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 119,217 | $ 118,786
Total Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 10.500 | 10.500
Total Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 10.00 | 10.00
Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 101,334 | $ 100,968
Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 95,374 | $ 95,029
Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 8.500 | 8.500
Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 8.00 | 8.00
Tier 1 Capital (to Average Assets), For Capital Adequacy Purposes Amount | $ 77,164 | $ 63,879
Tier 1 Capital (to Average Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 96,455 | $ 79,848
Tier 1 Capital (to Average Assets), For Capital Adequacy Purposes Ratio (as a percent) | 4.00 | 4.00
Tier 1 Capital (to Average Assets), To Be well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 5.00 | 5.00
Commerce Bank |  |
Capital Requirements |  |
Common Equity Tier 1 Capital (to Risk Weighted Assets), Actual Amount | $ 102,375 | $ 93,426
Common Equity Tier 1 Capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 46.06% | 35.64%
Total Capital (to Risk Weighted Assets), Actual Amount | $ 104,996 |
Total Capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 47.24 | 36.72
Tier 1 Capital (to Risk Weighted Assets), Actual Amount | $ 102,375 | $ 96,240
Tier 1 capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 46.06 | 35.64
Tier 1 Capital (to Average Assets), Actual Amount | $ 102,375 | $ 93,426
Tier 1 capital (to Average Assets), Actual Ratio (as a percent) | 16.10 | 16.69
Commerce Bank | Minimum |  |
Capital Requirements |  |
Common Equity Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 15,559 | $ 18,347
Common Equity Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 14,448 | $ 17,037
Common Equity Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 7.00% | 7.00%
Common Equity Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 6.50% | 6.50%
Total Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 23,339 | $ 27,521
Total Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 22,227 | $ 26,210
Total Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 10.500 | 10.500
Total Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 10.00 | 10.00
Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 18,893 | $ 22,279
Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 17,782 | $ 20,968
Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 8.500 | 8.500
Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 8.00 | 8.00
Tier 1 Capital (to Average Assets), For Capital Adequacy Purposes Amount | $ 25,441 | $ 22,394
Tier 1 Capital (to Average Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 31,801 | $ 27,993
Tier 1 Capital (to Average Assets), For Capital Adequacy Purposes Ratio (as a percent) | 4.00 | 4.00
Tier 1 Capital (to Average Assets), To Be well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 5.00 | 5.00
International Bank of Commerce Zapata |  |
Capital Requirements |  |
Common Equity Tier 1 Capital (to Risk Weighted Assets), Actual Amount | $ 75,303 | $ 71,369
Common Equity Tier 1 Capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 42.25% | 34.51%
Total Capital (to Risk Weighted Assets), Actual Amount | $ 77,354 | $ 73,510
Total Capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 43.40 | 35.55
Tier 1 Capital (to Risk Weighted Assets), Actual Amount | $ 75,303 | $ 71,369
Tier 1 capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 42.25 | 34.51
Tier 1 Capital (to Average Assets), Actual Amount | $ 75,303 | $ 71,369
Tier 1 capital (to Average Assets), Actual Ratio (as a percent) | 16.15 | 16.52
International Bank of Commerce Zapata | Minimum |  |
Capital Requirements |  |
Common Equity Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 12,475 | $ 14,476
Common Equity Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 11,584 | $ 13,442
Common Equity Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 7.00% | 7.00%
Common Equity Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 6.50% | 6.50%
Total Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 18,713 | $ 21,714
Total Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 17,822 | $ 20,680
Total Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 10.500 | 10.500
Total Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 10.00 | 10.00
Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 15,149 | $ 17,578
Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 14,258 | $ 16,544
Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 8.500 | 8.500
Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 8.00 | 8.00
Tier 1 Capital (to Average Assets), For Capital Adequacy Purposes Amount | $ 18,651 | $ 17,277
Tier 1 Capital (to Average Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 23,314 | $ 21,596
Tier 1 Capital (to Average Assets), For Capital Adequacy Purposes Ratio (as a percent) | 4.00 | 4.00
Tier 1 Capital (to Average Assets), To Be well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 5.00 | 5.00

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