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Capital Requirements (Capital Amounts and Ratios) (Details) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2015 | Dec. 31, 2014
Capital Requirements |  |
Total Capital (to Risk Weighted Assets), Actual Ratio (as a percent) |  | 20.24%
Tier 1 capital (to Risk Weighted Assets), Actual Ratio (as a percent) |  | 19.34%
Tier 1 capital (to Average Assets), Actual Ratio (as a percent) |  | 12.33%
Minimum |  |
Capital Requirements |  |
Total Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount |  | $ 602,847
Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount |  | 301,424
Tier 1 Capital (to Average Assets), For Capital Adequacy Purposes Amount |  | $ 472,864
Total Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) |  | 8.00%
Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) |  | 4.00%
Tier 1 Capital (to Average Assets), For Capital Adequacy Purposes Ratio (as a percent) |  | 4.00%
Parent Company |  |
Capital Requirements |  |
Common Equity Tier 1 Capital (to Risk Weighted Assets), Actual Amount | $ 1,380,801 |
Common Equity Tier 1 capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 16.81% |
Total Capital (to Risk Weighted Assets), Actual Amount | $ 1,605,419 | $ 1,524,998
Tier 1 Capital (to Risk Weighted Assets), Actual Amount | 1,535,443 | 1,457,068
Tier 1 Capital (to Average Assets), Actual Amount | $ 1,535,443 | 1,457,068
Total Capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 19.54% |
Tier 1 capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 18.69% |
Tier 1 capital (to Average Assets), Actual Ratio (as a percent) | 13.15% |
Parent Company | Minimum |  |
Capital Requirements |  |
Common Equity Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 369,726 |
Common Equity Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 4.50% |
Total Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 657,291 |
Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | 492,968 |
Tier 1 Capital (to Average Assets), For Capital Adequacy Purposes Amount | $ 466,897 |
Total Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 8.00% |
Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 6.00% |
Tier 1 Capital (to Average Assets), For Capital Adequacy Purposes Ratio (as a percent) | 4.00% |
International Bank of Commerce, Laredo |  |
Capital Requirements |  |
Common Equity Tier 1 Capital (to Risk Weighted Assets), Actual Amount | $ 1,151,812 |
Common Equity Tier 1 capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 16.42% |
Total Capital (to Risk Weighted Assets), Actual Amount | $ 1,213,377 | 1,131,528
Tier 1 Capital (to Risk Weighted Assets), Actual Amount | 1,151,812 | 1,071,360
Tier 1 Capital (to Average Assets), Actual Amount | $ 1,151,812 | $ 1,071,360
Total Capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 17.30% | 17.31%
Tier 1 capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 16.42% | 16.39%
Tier 1 capital (to Average Assets), Actual Ratio (as a percent) | 12.09% | 11.22%
International Bank of Commerce, Laredo | Minimum |  |
Capital Requirements |  |
Common Equity Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 315,707 |
Common Equity Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 456,022 |
Common Equity Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 4.50% |
Common Equity Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 6.50% |
Total Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 561,258 | $ 523,006
Total Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | 701,572 | 653,757
Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | 420,943 | 261,503
Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | 561,258 | 392,254
Tier 1 Capital (to Average Assets), For Capital Adequacy Purposes Amount | 381,105 | 381,804
Tier 1 Capital (to Average Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 476,381 | $ 477,255
Total Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 8.00% | 8.00%
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 Ratio (as a percent) | 6.00% | 4.00%
Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 8.00% | 6.00%
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 | $ 154,141 |
Common Equity Tier 1 capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 26.26% |
Total Capital (to Risk Weighted Assets), Actual Amount | $ 159,913 | $ 151,489
Tier 1 Capital (to Risk Weighted Assets), Actual Amount | 154,141 | 145,584
Tier 1 Capital (to Average Assets), Actual Amount | $ 154,141 | $ 145,584
Total Capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 27.24% | 28.60%
Tier 1 capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 26.26% | 27.48%
Tier 1 capital (to Average Assets), Actual Ratio (as a percent) | 15.03% | 13.96%
International Bank of Commerce, Brownsville | Minimum |  |
Capital Requirements |  |
Common Equity Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 26,418 |
Common Equity Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 38,159 |
Common Equity Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 4.50% |
Common Equity Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 6.50% |
Total Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 46,965 | $ 42,381
Total Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | 58,706 | 52,976
Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | 35,224 | 21,190
Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | 46,965 | 31,785
Tier 1 Capital (to Average Assets), For Capital Adequacy Purposes Amount | 41,034 | 41,717
Tier 1 Capital (to Average Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 51,293 | $ 52,146
Total Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 8.00% | 8.00%
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 Ratio (as a percent) | 6.00% | 4.00%
Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 8.00% | 6.00%
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 | $ 66,153 |
Common Equity Tier 1 capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 35.71% |
Total Capital (to Risk Weighted Assets), Actual Amount | $ 67,470 | $ 60,946
Tier 1 Capital (to Risk Weighted Assets), Actual Amount | 66,153 | 60,035
Tier 1 Capital (to Average Assets), Actual Amount | $ 66,153 | $ 60,035
Total Capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 36.42% | 33.83%
Tier 1 capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 35.71% | 33.33%
Tier 1 capital (to Average Assets), Actual Ratio (as a percent) | 13.15% | 10.88%
International Bank of Commerce, Zapata | Minimum |  |
Capital Requirements |  |
Common Equity Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 8,336 |
Common Equity Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 12,042 |
Common Equity Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 4.50% |
Common Equity Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 6.50% |
Total Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 14,820 | $ 14,412
Total Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | 18,525 | 18,041
Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | 11,115 | 7,206
Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | 14,820 | 10,809
Tier 1 Capital (to Average Assets), For Capital Adequacy Purposes Amount | 20,129 | 22,081
Tier 1 Capital (to Average Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 25,161 | $ 27,602
Total Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 8.00% | 8.00%
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 Ratio (as a percent) | 6.00% | 4.00%
Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 8.00% | 6.00%
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 | $ 72,882 |
Common Equity Tier 1 capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 36.17% |
Total Capital (to Risk Weighted Assets), Actual Amount | $ 74,204 | $ 68,291
Tier 1 Capital (to Risk Weighted Assets), Actual Amount | 72,882 | 67,347
Tier 1 Capital (to Average Assets), Actual Amount | $ 72,882 | $ 67,347
Total Capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 36.83% | 37.42%
Tier 1 capital (to Risk Weighted Assets), Actual Ratio (as a percent) | 36.17% | 36.90%
Tier 1 capital (to Average Assets), Actual Ratio (as a percent) | 12.94% | 12.04%
Commerce Bank | Minimum |  |
Capital Requirements |  |
Common Equity Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 9,067 |
Common Equity Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 13,097 |
Common Equity Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 4.50% |
Common Equity Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 6.50% |
Total Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | $ 16,119 | $ 14,600
Total Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | 20,149 | 18,251
Tier 1 Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Amount | 12,089 | 7,300
Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | 16,119 | 10,950
Tier 1 Capital (to Average Assets), For Capital Adequacy Purposes Amount | 22,521 | 22,373
Tier 1 Capital (to Average Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 28,151 | $ 27,966
Total Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent) | 8.00% | 8.00%
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 Ratio (as a percent) | 6.00% | 4.00%
Tier 1 Capital (to Risk Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (as a percent) | 8.00% | 6.00%
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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- Definition The minimum amount of Tier 1 Leverage Capital for capital adequacy purposes divided by average assets as defined in the regulations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958568-112826 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=35709795&loc=d3e65071-112826 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958570-112826 + Details
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- Definition The amount of Tier 1 Leverage Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958568-112826 + Details
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- Definition Tier 1 Risk Based Capital as defined in the regulations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958568-112826 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=35709795&loc=d3e65071-112826 + Details
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- Definition The minimum Tier One Capital Ratio (Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958568-112826 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958570-112826 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=35709795&loc=d3e65071-112826 + Details
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- Definition The amount of Tier 1 Risk Based Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958568-112826 + Details
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- Definition The Tier 1 capital ratio (Tier 1 capital divided by risk weighted assets) required to be categorized as "well capitalized" under the regulatory framework for prompt corrective action. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958568-112826 + Details
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