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Business Segments and Revenue from Contracts with Customers - Additional Information (Detail) $ in Millions | 12 Months Ended
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Dec. 31, 2019 USD ($) Segment | Dec. 31, 2018 USD ($)
Segment Reporting Information [Line Items] |  |
Number of operating segments | Segment | 3 |
Commercial Banking | Minimum |  |
Segment Reporting Information [Line Items] |  |
Customer net revenue range | $ 20 |
Commercial Banking | Maximum |  |
Segment Reporting Information [Line Items] |  |
Customer net revenue range | $ 2,000 |
Operating segments | Commercial Banking |  |
Segment Reporting Information [Line Items] |  |
Revenue change due to impact of federal tax rate |  | $ (108)

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- Definition Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues. + References No definition available. + Details
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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. + References No definition available. + Details
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- Details
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- Details
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