Accounting Policies [Line Items]

No definition available.

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- Definition

the period over which loan acquisition costs are amortized.

+ References

No definition available.

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- Definition

Period following reciept of notification of bankruptcy and probate accounts, after which these accounts are charged off.

+ References

No definition available.

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- Definition

Cash and Cash Equivalents Maturity Period

+ References

No definition available.

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- Definition

Credit Card Rewards Cost Adjusted For Estimated Forfeitures

+ References

No definition available.

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- Definition

Credit Card Rewards Liability Net

+ References

No definition available.

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- Definition

Delinquent Loan Qualification Period

+ References

No definition available.

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- Definition

Receivables associated with alleged or potential fraudulent transactions are adjusted to net realizable value upon notification at the end of the month 90 days following notification.

+ References

No definition available.

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- Definition

Unamortrized deferred incentive payments.

+ References

No definition available.

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- Definition

Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 720
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-Section 50
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- Definition

Amount before accumulated amortization of capitalized costs for computer software, including but not limited to, acquired and internally developed computer software.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481283/985-20-50-1

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- Definition

For banks and other depository institutions: Includes cash on hand (currency and coin), cash items in process of collection, noninterest bearing deposits due from other financial institutions (including corporate credit unions), and noninterest bearing balances with the Federal Reserve Banks, Federal Home Loan Banks and central banks.

+ References

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- Definition

Amount, after accumulated amortization and related credit card fees, of credit card origination costs not related to private label credit cards.

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- Definition

Unearned discounts (other than cash or quantity discounts and the like), finance charges, and interest included in the face amount of receivables, that are shown as a deduction from the related receivables. For example, 1) finance charges booked as a receivable when a loan is made and recognized as income at a later date; and 2) interest charges deducted from the face loan amount, resulting in a discounted amount actually advanced to the borrower (wherein the receivable includes the amount actually advanced to the borrower and the as yet unearned interest income).

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- Definition

Threshold period for when financing receivable is considered past due to write off as uncollectible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

For banks and other depository institutions (including Federal Reserve Banks, if applicable): Interest-bearing deposits in other financial institutions for relatively short periods of time including, for example, certificates of deposits, which are presented separately from cash on the balance sheet.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

+ References

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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Summary of Significant Accounting Policies (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Accounting Policies [Line Items]
Cash and due from banks	$ 2,000	$ 1,500
Interest-earning deposits at other banks	$ 9,700	7,400
Threshold charge-off period for bankruptcy and probate accounts	60 days
Fraudulent transaction charge off period	90 days
Off-Balance sheet, credit loss, liability	$ 0
Capitalized Computer Software, Gross	0
Advertising costs	359	307	$ 262
Deferred revenues related to balance transfer fees	107	85
Unamortized deferred costs for loan origination	306	298
Credit card rewards cost	3,100	3,000	$ 2,500
Liability for customer rewards	2,200	2,200
Unamortized portion of the deferred incentive payments	$ 27	$ 32
Retirement Eligible [Member]
Accounting Policies [Line Items]
Amortization of share-based compensation in accordance with vesting terms	12 months
Building [Member]
Accounting Policies [Line Items]
Premises and equipment, useful life	39 years
Minimum [Member]
Accounting Policies [Line Items]
Delinquent loan qualification period	30 days
Minimum [Member] \| Improvements [Member]
Accounting Policies [Line Items]
Premises and equipment, useful life	10 years
Minimum [Member] \| Furniture and Fixtures [Member]
Accounting Policies [Line Items]
Premises and equipment, useful life	5 years
Minimum [Member] \| Equipment [Member]
Accounting Policies [Line Items]
Premises and equipment, useful life	3 years
Minimum [Member] \| Software Development [Member]
Accounting Policies [Line Items]
Premises and equipment, useful life	3 years
Maximum [Member]
Accounting Policies [Line Items]
Cash and cash equivalents maturity period	90 days
Maximum [Member] \| Improvements [Member]
Accounting Policies [Line Items]
Premises and equipment, useful life	15 years
Maximum [Member] \| Furniture and Fixtures [Member]
Accounting Policies [Line Items]
Premises and equipment, useful life	10 years
Maximum [Member] \| Equipment [Member]
Accounting Policies [Line Items]
Premises and equipment, useful life	10 years
Maximum [Member] \| Software Development [Member]
Accounting Policies [Line Items]
Premises and equipment, useful life	10 years
Credit Card Loans [Member]
Accounting Policies [Line Items]
Threshold charge-off period for past due accounts (in days)	180 days
Amortization period for loan origination costs	1 year
Personal And Private Student Loan Member [Member]
Accounting Policies [Line Items]
Threshold charge-off period for past due accounts (in days)	120 days