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Capital Requirements (Capital Amounts and Ratios) (Details) - USD ($) $ in Thousands | Dec. 31, 2022 | Dec. 31, 2021
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Parent Company |  |
Capital Requirements |  |
Common Equity Tier 1 Capital (to Risk Weighted Assets), Actual Amount | $ 2,232,723 | $ 2,057,928
Common Equity Tier 1 Capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 0.2021% | 0.2047%
Total Capital (to Risk Weighted Assets), Actual Amount | $ 2,455,468 | $ 2,284,579
Total Capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 0.2222 | 0.2273
Tier 1 Capital (to Risk Weighted Assets), Actual Amount | $ 2,324,903 | $ 2,170,682
Tier 1 capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 0.2104 | 0.2159
Tier 1 Capital (to Average Assets), Actual Amount | $ 2,324,903 | $ 2,170,682
Tier 1 capital (to Average Assets), Actual Ratio (as a percent) | 0.1459 | 0.1394
Parent Company | Minimum |  |
Capital Requirements |  |
Common Equity Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 773,398 | $ 703,710
Common Equity Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 0.07% | 0.07%
Total Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 1,160,096 | $ 1,055,565
Total Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 0.10500 | 0.10500
Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 939,126 | $ 854,505
Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 0.08500 | 0.08500
Tier 1 Capital (to Average Assets), For Capital Adequacy Purposes Amount | $ 637,578 | $ 622,671
Tier 1 Capital (to Average Assets), For Capital Adequacy Purposes Ratio (as a percent) | 0.0400 | 0.0400
International Bank of Commerce Laredo |  |
Capital Requirements |  |
Common Equity Tier 1 Capital (to Risk Weighted Assets), Actual Amount | $ 1,310,616 | $ 1,287,687
Common Equity Tier 1 Capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 0.1807% | 0.1974%
Total Capital (to Risk Weighted Assets), Actual Amount | $ 1,401,298 | $ 1,367,487
Total Capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 0.1932 | 0.2097
Tier 1 Capital (to Risk Weighted Assets), Actual Amount | $ 1,310,616 | $ 1,287,687
Tier 1 capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 0.1807 | 0.1974
Tier 1 Capital (to Average Assets), Actual Amount | $ 1,310,616 | $ 1,287,687
Tier 1 capital (to Average Assets), Actual Ratio (as a percent) | 0.1309 | 0.1114
International Bank of Commerce Laredo | Minimum |  |
Capital Requirements |  |
Common Equity Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 507,625 | $ 456,544
Common Equity Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 471,366 | $ 423,934
Common Equity Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 0.07% | 0.07%
Common Equity Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 0.065% | 0.065%
Total Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 761,438 | $ 684,816
Total Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 725,179 | $ 652,206
Total Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 0.10500 | 0.10500
Total Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 0.1000 | 0.1000
Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 616,402 | $ 554,375
Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 580,143 | $ 521,764
Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 0.08500 | 0.08500
Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 0.0800 | 0.0800
Tier 1 Capital (to Average Assets), For Capital Adequacy Purposes Amount | $ 400,489 | $ 462,225
Tier 1 Capital (to Average Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 500,611 | $ 577,781
Tier 1 Capital (to Average Assets), For Capital Adequacy Purposes Ratio (as a percent) | 0.0400 | 0.0400
Tier 1 Capital (to Average Assets), To Be well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 0.0500 | 0.0500
International Bank of Commerce Brownsville |  |
Capital Requirements |  |
Common Equity Tier 1 Capital (to Risk Weighted Assets), Actual Amount | $ 363,093 | $ 221,567
Common Equity Tier 1 Capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 0.2086% | 0.1859%
Total Capital (to Risk Weighted Assets), Actual Amount | $ 383,804 | $ 232,454
Total Capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 0.2205 | 0.1950
Tier 1 Capital (to Risk Weighted Assets), Actual Amount | $ 363,093 | $ 221,567
Tier 1 capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 0.2086 | 0.1859
Tier 1 Capital (to Average Assets), Actual Amount | $ 363,093 | $ 221,567
Tier 1 capital (to Average Assets), Actual Ratio (as a percent) | 0.0895 | 0.1149
International Bank of Commerce Brownsville | Minimum |  |
Capital Requirements |  |
Common Equity Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 121,855 | $ 83,452
Common Equity Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 113,151 | $ 77,491
Common Equity Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 0.07% | 0.07%
Common Equity Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 0.065% | 0.065%
Total Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 182,782 | $ 125,178
Total Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 174,078 | $ 119,217
Total Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 0.10500 | 0.10500
Total Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 0.1000 | 0.1000
Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 147,966 | $ 101,334
Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 139,262 | $ 95,374
Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 0.08500 | 0.08500
Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 0.0800 | 0.0800
Tier 1 Capital (to Average Assets), For Capital Adequacy Purposes Amount | $ 162,246 | $ 77,164
Tier 1 Capital (to Average Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 202,808 | $ 96,455
Tier 1 Capital (to Average Assets), For Capital Adequacy Purposes Ratio (as a percent) | 0.0400 | 0.0400
Tier 1 Capital (to Average Assets), To Be well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 0.0500 | 0.0500
International Bank Of Commerce Oklahoma |  |
Capital Requirements |  |
Common Equity Tier 1 Capital (to Risk Weighted Assets), Actual Amount | $ 232,689 | $ 315,957
Common Equity Tier 1 Capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 0.2117% | 0.198%
Total Capital (to Risk Weighted Assets), Actual Amount | $ 243,739 | $ 334,495
Total Capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 0.2218 | 0.2096
Tier 1 Capital (to Risk Weighted Assets), Actual Amount | $ 232,689 | $ 315,957
Tier 1 capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 0.2117 | 0.1980
Tier 1 Capital (to Average Assets), Actual Amount | $ 232,689 | $ 315,957
Tier 1 capital (to Average Assets), Actual Ratio (as a percent) | 0.1348 | 0.2017
International Bank Of Commerce Oklahoma | Minimum |  |
Capital Requirements |  |
Common Equity Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 76,941 | $ 111,690
Common Equity Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 71,445 | $ 103,712
Common Equity Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 0.07% | 0.07%
Common Equity Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 0.065% | 0.065%
Total Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 115,412 | $ 167,535
Total Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 109,916 | $ 159,557
Total Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 0.10500 | 0.10500
Total Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 0.1000 | 0.1000
Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 93,429 | $ 135,623
Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 87,933 | $ 127,645
Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 0.08500 | 0.08500
Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 0.0800 | 0.0800
Tier 1 Capital (to Average Assets), For Capital Adequacy Purposes Amount | $ 69,028 | $ 62,663
Tier 1 Capital (to Average Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 86,286 | $ 78,329
Tier 1 Capital (to Average Assets), For Capital Adequacy Purposes Ratio (as a percent) | 0.0400 | 0.0400
Tier 1 Capital (to Average Assets), To Be well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 0.0500 | 0.0500
Commerce Bank |  |
Capital Requirements |  |
Common Equity Tier 1 Capital (to Risk Weighted Assets), Actual Amount | $ 98,087 | $ 75,303
Common Equity Tier 1 Capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 0.4226% | 0.4225%
Total Capital (to Risk Weighted Assets), Actual Amount | $ 100,798 |
Total Capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 0.4343 | 0.4340
Tier 1 Capital (to Risk Weighted Assets), Actual Amount | $ 98,087 | $ 77,354
Tier 1 capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 0.4226 | 0.4225
Tier 1 Capital (to Average Assets), Actual Amount | $ 98,087 | $ 75,303
Tier 1 capital (to Average Assets), Actual Ratio (as a percent) | 0.1439 | 0.1615
Commerce Bank | Minimum |  |
Capital Requirements |  |
Common Equity Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 16,248 | $ 12,475
Common Equity Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 15,088 | $ 11,584
Common Equity Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 0.07% | 0.07%
Common Equity Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 0.065% | 0.065%
Total Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 24,372 | $ 18,713
Total Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 23,212 | $ 17,822
Total Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 0.10500 | 0.10500
Total Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 0.1000 | 0.1000
Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 19,730 | $ 15,149
Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 18,569 | $ 14,258
Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 0.08500 | 0.08500
Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 0.0800 | 0.0800
Tier 1 Capital (to Average Assets), For Capital Adequacy Purposes Amount | $ 27,270 | $ 18,651
Tier 1 Capital (to Average Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 34,088 | $ 23,314
Tier 1 Capital (to Average Assets), For Capital Adequacy Purposes Ratio (as a percent) | 0.0400 | 0.0400
Tier 1 Capital (to Average Assets), To Be well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 0.0500 | 0.0500
International Bank of Commerce Zapata |  |
Capital Requirements |  |
Common Equity Tier 1 Capital (to Risk Weighted Assets), Actual Amount | $ 71,418 | $ 102,375
Common Equity Tier 1 Capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 0.377% | 0.4606%
Total Capital (to Risk Weighted Assets), Actual Amount | $ 73,420 | $ 104,996
Total Capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 0.3876 | 0.4724
Tier 1 Capital (to Risk Weighted Assets), Actual Amount | $ 71,418 | $ 102,375
Tier 1 capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 0.3770 | 0.4606
Tier 1 Capital (to Average Assets), Actual Amount | $ 71,418 | $ 102,375
Tier 1 capital (to Average Assets), Actual Ratio (as a percent) | 0.1500 | 0.1610
International Bank of Commerce Zapata | Minimum |  |
Capital Requirements |  |
Common Equity Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 13,261 | $ 15,559
Common Equity Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 12,314 | $ 14,448
Common Equity Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 0.07% | 0.07%
Common Equity Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 0.065% | 0.065%
Total Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 19,892 | $ 23,339
Total Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 18,945 | $ 22,227
Total Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 0.10500 | 0.10500
Total Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 0.1000 | 0.1000
Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 16,103 | $ 18,893
Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 15,156 | $ 17,782
Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 0.08500 | 0.08500
Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 0.0800 | 0.0800
Tier 1 Capital (to Average Assets), For Capital Adequacy Purposes Amount | $ 19,048 | $ 25,441
Tier 1 Capital (to Average Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 23,811 | $ 31,801
Tier 1 Capital (to Average Assets), For Capital Adequacy Purposes Ratio (as a percent) | 0.0400 | 0.0400
Tier 1 Capital (to Average Assets), To Be well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 0.0500 | 0.0500

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- Definition Amount of minimum Tier 1 risk-based capital required for capital adequacy with capital conservation buffer, as defined by regulatory framework. + References No definition available. + Details
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