Fee-based Revenue from Contracts with Customers - Retail Banking Noninterest Income Disaggregation (Details) $ in Millions	12 Months Ended
Dec. 31, 2021 USD ($) segment	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Revenue from Contract with Customer [Abstract]
Number of reportable segments \| segment	3
Disaggregation of Revenue [Line Items]
Noninterest income	$ 8,564	$ 6,955	$ 6,874
Brokerage fees
Disaggregation of Revenue [Line Items]
Noninterest income	9
Retail Banking
Disaggregation of Revenue [Line Items]
Noninterest income	2,796	2,519	2,648
Retail Banking \| In-Scope Retail Banking Noninterest Income
Disaggregation of Revenue [Line Items]
Noninterest income	2,285	1,910	2,190
Retail Banking \| Out-of-Scope Retail Banking Noninterest Income
Disaggregation of Revenue [Line Items]
Noninterest income	511	609	458
Retail Banking \| Debit card fees \| In-Scope Retail Banking Noninterest Income
Disaggregation of Revenue [Line Items]
Noninterest income	665	522	535
Retail Banking \| Deposit account fees \| In-Scope Retail Banking Noninterest Income
Disaggregation of Revenue [Line Items]
Noninterest income	490	463	642
Retail Banking \| Brokerage fees \| In-Scope Retail Banking Noninterest Income
Disaggregation of Revenue [Line Items]
Noninterest income	464	367	356
Retail Banking \| Net credit card fees \| In-Scope Retail Banking Noninterest Income
Disaggregation of Revenue [Line Items]
Noninterest income	221	179	186
Interchange fees	582	469	498
Credit card reward costs	361	290	312
Retail Banking \| Merchant services \| In-Scope Retail Banking Noninterest Income
Disaggregation of Revenue [Line Items]
Noninterest income	174	154	216
Retail Banking \| Other \| In-Scope Retail Banking Noninterest Income
Disaggregation of Revenue [Line Items]
Noninterest income	$ 271	$ 225	$ 255

Credit Card Reward Costs

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- Definition

Interchange Fees

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The total amount of noninterest income which may be derived from: (1) fees and commissions; (2) premiums earned; (3) insurance policy charges; (4) the sale or disposal of assets; and (5) other sources not otherwise specified.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.13)
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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8672-108599

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