XML 71 R53.htm IDEA: XBRL DOCUMENT
v3.22.0.1

Regulatory Capital and Reserve Requirements Regulatory Capital and Reserve Requirements (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2021
Broker-Dealer, Net Capital Requirement, SEC Regulation [Abstract] |
Summary of Capital Position | The following is a summary of the capital position of the Corporation and Comerica Bank, its principal banking subsidiary.
(dollar amounts in millions) | Comerica Incorporated (Consolidated) |  | Comerica Bank
December 31, 2021 |  |  |
CET1 capital (minimum $3.1 billion (Consolidated)) | $ | 7,064 |  |  | $ | 7,634 |
Tier 1 capital (minimum $4.2 billion (Consolidated)) | 7,458 |  |  | 7,634 |
Total capital (minimum $5.6 billion (Consolidated)) | 8,608 |  |  | 8,584 |
Risk-weighted assets | 69,708 |  |  | 69,542 |
Average assets (fourth quarter) | 96,417 |  |  | 96,216 |
CET1 capital to risk-weighted assets (minimum-4.5%) | 10.13 | % |  | 10.98 | %
Tier 1 capital to risk-weighted assets (minimum-6.0%) | 10.70 |  |  | 10.98 |
Total capital to risk-weighted assets (minimum-8.0%) | 12.35 |  |  | 12.34 |
Tier 1 capital to average assets (minimum-4.0%) | 7.74 |  |  | 7.93 |
Capital conservation buffer (minimum-2.5%) | 4.35 |  |  | 4.34 |
December 31, 2020 |  |  |
CET1 capital (minimum $3.0 billion (Consolidated)) | $ | 6,919 |  |  | $ | 7,278 |
Tier 1 capital (minimum $4.0 billion (Consolidated)) | 7,313 |  |  | 7,278 |
Total capital (minimum $5.4 billion (Consolidated)) | 8,833 |  |  | 8,547 |
Risk-weighted assets | 66,931 |  |  | 66,759 |
Average assets (fourth quarter) | 84,705 |  |  | 84,536 |
CET1 capital to risk-weighted assets (minimum-4.5%) | 10.34 | % |  | 10.90 | %
Tier 1 capital to risk-weighted assets (minimum-6.0%) | 10.93 |  |  | 10.90 |
Total capital to risk-weighted assets (minimum-8.0%) | 13.20 |  |  | 12.80 |
Tier 1 capital to average assets (minimum-4.0%) | 8.63 |  |  | 8.61 |
Capital conservation buffer (minimum-2.5%) | 4.93 |  |  | 4.80 |

X
- References No definition available. + Details
Name: | srt_RegulatoryCapitalRequirementsAbstract
Namespace Prefix: | srt_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of the capital amounts and ratios as of the balance sheet date, indicating whether the entity or entities are in compliance with regulatory capital requirements, by entity. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=117337116&loc=SL5958570-112826 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=117337116&loc=SL5958568-112826 + Details
Name: | us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTextBlock
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration