Intangible Assets - Narrative (Details) - USD ($) $ in Millions |
3 Months Ended | ||
|---|---|---|---|
Feb. 01, 2026 |
Mar. 31, 2026 |
Mar. 31, 2025 |
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| Finite-Lived Intangible Assets | |||
| Amortization expense | $ 45 | $ 8 | |
| Comerica Incorporated | |||
| Finite-Lived Intangible Assets | |||
| Acquired finite-lived intangible asset | $ 1,209 | ||
| Core deposit intangibles | Comerica Incorporated | |||
| Finite-Lived Intangible Assets | |||
| Acquired finite-lived intangible asset | $ 1,200 | ||
| Weighted-average useful life, acquired finite-lived intangible assets | 10 years | ||
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- Definition Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of identifiable intangible asset acquired in business combination and recognized at acquisition date. Excludes goodwill and financial asset. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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