Parent Company Condensed Financial Information (Schedule of Parent Company Condensed Statements of Financial Condition) (Details) - USD ($) $ in Millions |
Dec. 31, 2023 |
Sep. 30, 2023 |
Jun. 30, 2023 |
Mar. 31, 2023 |
Dec. 31, 2022 |
Dec. 31, 2021 |
Dec. 31, 2020 |
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| Assets | |||||||||||||
| Cash and cash equivalents | $ 11,685 | $ 8,856 | $ 8,750 | ||||||||||
| Restricted cash | 43 | 41 | 2,582 | ||||||||||
| Net loan receivables | 119,126 | 104,746 | |||||||||||
| Other assets | 5,858 | $ 5,696 | $ 4,975 | $ 4,610 | 4,742 | ||||||||
| Total assets | 151,713 | 143,615 | 138,235 | 133,290 | 131,851 | ||||||||
| Liabilities and Stockholders’ Equity | |||||||||||||
| Non-interest-bearing deposit accounts | 1,438 | 1,485 | |||||||||||
| Long-term borrowings | 20,581 | 20,108 | |||||||||||
| Accrued expenses and other liabilities | 7,216 | 6,464 | 5,590 | 5,789 | 6,212 | ||||||||
| Total liabilities | 137,478 | 129,950 | 124,853 | 119,692 | 117,956 | ||||||||
| Stockholders’ equity | 14,235 | 13,665 | 13,382 | 13,598 | 13,895 | 12,789 | $ 10,326 | ||||||
| Total liabilities and stockholders’ equity | 151,713 | $ 143,615 | $ 138,235 | $ 133,290 | 131,851 | ||||||||
| Parent Company [Member] | |||||||||||||
| Assets | |||||||||||||
| Cash and cash equivalents | 3,509 | [1] | 3,155 | [1] | 3,182 | ||||||||
| Restricted cash | 75 | 20 | $ 20 | ||||||||||
| Net loan receivables | $ 1,650 | [2] | $ 1,759 | ||||||||||
| Financing Receivable, after Allowance for Credit Loss, Related Party, Type [Extensible Enumeration] | Subsidiaries | Subsidiaries | |||||||||||
| Investment in bank subsidiary | $ 12,340 | $ 11,279 | |||||||||||
| Investments in non-bank subsidiaries | 974 | 834 | |||||||||||
| Other assets | 871 | 811 | |||||||||||
| Total assets | 19,419 | 17,858 | |||||||||||
| Liabilities and Stockholders’ Equity | |||||||||||||
| Non-interest-bearing deposit accounts | 2 | 2 | |||||||||||
| Long-term borrowings | 4,469 | 3,487 | |||||||||||
| Accrued expenses and other liabilities | 323 | 359 | |||||||||||
| Total liabilities | 5,184 | 3,963 | |||||||||||
| Stockholders’ equity | 14,235 | 13,895 | |||||||||||
| Total liabilities and stockholders’ equity | 19,419 | 17,858 | |||||||||||
| Parent Company [Member] | Subsidiaries | |||||||||||||
| Liabilities and Stockholders’ Equity | |||||||||||||
| Short-term borrowings from subsidiaries | 390 | 115 | |||||||||||
| Parent Company [Member] | Discover Bank [Member] | |||||||||||||
| Liabilities and Stockholders’ Equity | |||||||||||||
| Liquidity available to parent from money market deposit account at subsidiary | 3,500 | 3,100 | |||||||||||
| Liquidity available to parent from funds advanced to subsidiary | $ 1,300 | $ 1,300 | |||||||||||
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- Definition Investments in bank subsidiaries No definition available.
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- Definition Total investments in non-bank subsidiaries. No definition available.
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- Definition The amount of liquidity available to the parent company from funds advanced to a subsidiary. No definition available.
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- Definition Liquidity Available to Parent from Money Market Deposit Account at Subsidiary No definition available.
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- Definition Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- Definition Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Indicates type of related party for financing receivable, after allowance for credit loss. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Sum of the carrying amounts as of the balance sheet date of all liabilities that are recognized. Liabilities are probable future sacrifices of economic benefits arising from present obligations of an entity to transfer assets or provide services to other entities in the future. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of liabilities and equity items, including the portion of equity attributable to noncontrolling interests, if any. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- References No definition available.
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- Definition Amount of long-term debt and lease obligation, classified as noncurrent. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The aggregate amount of all domestic and foreign noninterest-bearing deposits liabilities held by the entity. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amortized cost, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of assets classified as other. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of cash and cash equivalents restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of equity (deficit) attributable to parent. Excludes temporary equity and equity attributable to noncontrolling interest. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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