Discover Financial Services (DFS) 10-Q 1 May 24 2024 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2024	Apr. 26, 2024
Cover [Abstract]
Document type	10-Q
Document quarterly report	true
Document period end date	Mar. 31, 2024
Document transition report	false
Entity file number	001-33378
Entity registrant name	DISCOVER FINANCIAL SERVICES
Entity incorporation, state	DE
Entity tax identification number	36-2517428
Entity address, address line one	2500 Lake Cook Road
Entity address, city or town	Riverwoods
Entity address, state or province	IL
Entity address, postal zip code	60015
Entity phone number, city area code	224
Entity phone number, local phone number	405-0900
Title of 12(b) security	Common Stock, par value $0.01 per share
Trading symbol	DFS
Security exchange name	NYSE
Entity current reporting status	Yes
Entity interactive data current	Yes
Entity filer category	Large Accelerated Filer
Smaller reporting company	false
Emerging growth company	false
Entity shell company	false
Entity common stock, shares outstanding		250,599,037
Entity central index key	0001393612
Current fiscal year end date	--12-31
Document fiscal year focus	2024
Document fiscal period focus	Q1
Amendment flag	false

Condensed Consolidated Statemen

Condensed Consolidated Statements of Financial Condition - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Assets
Cash and cash equivalents	$ 14,004	$ 11,685
Restricted cash	439	43
Investment securities (includes available-for-sale securities of $13,261 and $13,402 reported at fair value with associated amortized cost of $13,439 and $13,451 at March 31, 2024 and December 31, 2023, respectively)	13,522	13,655
Loan receivables
Loan receivables	126,555	128,409
Allowance for credit losses	(9,258)	(9,283)
Net loan receivables	117,297	119,126
Premises and equipment, net	1,107	1,091
Goodwill	255	255
Other assets	6,065	5,667
Total assets	152,689	151,522
Deposits
Interest-bearing deposit accounts	108,930	107,493
Non-interest bearing deposit accounts	1,500	1,438
Total deposits	110,430	108,931
Short-term borrowings	0	750
Long-term borrowings	20,475	20,581
Accrued expenses and other liabilities	7,064	6,432
Total liabilities	137,969	136,694
Commitments, contingencies and guarantees (Notes 9, 12 and 13)
Stockholders' Equity
Common stock, par value $0.01 per share; 2,000,000,000 shares authorized; 571,594,531 and 570,837,720 shares issued at March 31, 2024 and December 31, 2023, respectively	6	6
Preferred stock, par value $0.01 per share; 200,000,000 shares authorized; 10,700 shares issued and outstanding at March 31, 2024 and December 31, 2023, respectively	1,056	1,056
Additional paid-in capital	4,578	4,553
Retained earnings	30,511	30,448
Accumulated other comprehensive loss	(393)	(225)
Treasury stock, at cost; 320,996,125 and 320,734,860 shares at March 31, 2024 and December 31, 2023, respectively	(21,038)	(21,010)
Total stockholders' equity	14,720	14,828
Total liabilities and stockholders' equity	152,689	151,522
Variable Interest Entity, Primary Beneficiary [Member]
Assets
Restricted cash	439	43
Loan receivables
Loan receivables	29,192	30,590
Allowance for credit losses	(1,323)	(1,347)
Other assets	4	3
Deposits
Short- and long-term borrowings	10,933	11,743
Accrued expenses and other liabilities	$ 17	$ 19

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Financial Condition (Parenthetical) - USD ($) $ in Millions		Mar. 31, 2024	Dec. 31, 2023
Statement of Financial Position [Abstract]
Available-for-sale investment securities, fair value	[1]	$ 13,261	$ 13,402
Available-for-sale investment securities, amortized cost	[1]	$ 13,439	$ 13,451
Common Stock, Par or Stated Value Per Share		$ 0.01	$ 0.01
Common Stock, Shares Authorized		2,000,000,000	2,000,000,000
Common Stock, Shares, Issued		571,594,531	570,837,720
Preferred stock, par or stated value per Share		$ 0.01	$ 0.01
Preferred Stock, Shares Authorized		200,000,000	200,000,000
Preferred Stock, Shares Issued		10,700	10,700
Preferred Stock, Shares Outstanding		10,700	10,700
Treasury Stock, Common, Shares		320,996,125	320,734,860
[1] Available-for-sale investment securities are reported at fair value.

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Income - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Interest income
Credit card loans	$ 3,938	$ 3,321
Other loans	712	564
Investment securities	124	101
Other interest income	174	91
Total interest income	4,948	4,077
Interest expense
Deposits	1,210	756
Short-term borrowings	6	0
Long-term borrowings	245	189
Total interest expense	1,461	945
Net interest income	3,487	3,132
Provision for credit losses	1,497	1,102
Net interest income after provision for credit losses	1,990	2,030
Other income
Discount and interchange revenue, net	371	330
Protection products revenue	42	43
Loan fee income	200	166
Transaction processing revenue	87	67
Gains (losses) on equity investments	0	(18)
Other income	23	22
Total other income	723	610
Other expense
Employee compensation and benefits	671	625
Marketing and business development	250	241
Information processing and communications	163	139
Professional fees	292	232
Premises and equipment	20	22
Other expense	913	124
Total other expense	2,309	1,383
Income before income taxes	404	1,257
Income tax expense	96	289
Net income	308	968
Net income allocated to common stockholders	$ 274	$ 931
Basic earnings per common share	$ 1.10	$ 3.55
Diluted earnings per common share	$ 1.10	$ 3.55

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Statement of Comprehensive Income [Abstract]
Net income	$ 308	$ 968
Other comprehensive (loss) income, net of tax
Unrealized (losses) gains on available-for-sale investment securities, net of tax	(97)	92
Unrealized (losses) gains on cash flow hedges, net of tax	(71)	12
Other comprehensive (loss) income	(168)	104
Comprehensive income	$ 140	$ 1,072

Condensed Consolidated Statem_5

Condensed Consolidated Statements of Changes in Stockholders' Equity - USD ($) $ in Millions	Total	Cumulative Effect, Period of Adoption, Adjustment	Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Retained Earnings [Member] Cumulative Effect, Period of Adoption, Adjustment	Accumulated Other Comprehensive (Loss) Income [Member]	Treasury Stock, Common	Series C Preferred Stock [Member]	Series C Preferred Stock [Member] Retained Earnings [Member]	Series D Preferred Stock	Series D Preferred Stock Retained Earnings [Member]
Preferred stock, shares outstanding, balance at beginning of period (in shares) at Dec. 31, 2022			11,000
Common stock, shares outstanding, balance at beginning of period (in shares) at Dec. 31, 2022				569,689,000
Stockholders' equity, balance at beginning of period at Dec. 31, 2022	$ 14,344		$ 1,056	$ 6	$ 4,468	$ 28,207		$ (339)	$ (19,054)
Stockholders' equity, balance at beginning of period (Accounting Standards Update 2022-02) at Dec. 31, 2022		$ 52					$ 52
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	968					968
Other comprehensive loss	104							104
Purchases of treasury stock	(1,243)								(1,243)
Common stock issued under employee benefit plans (in shares)				29,000
Common stock issued under employee benefit plans	3			$ 0	3
Shares Issued, Shares, Share-based Payment Arrangement, after Forfeiture				742,000
Common stock issued and stock-based compensation expense	22			$ 0	22
Dividends — common stock	(159)					(159)
Dividends — preferred stock										$ (16)	$ (16)	$ (15)	$ (15)
Preferred stock, shares outstanding, balance at end of period (in shares) at Mar. 31, 2023			11,000
Common stock, shares outstanding, balance at end of period (in shares) at Mar. 31, 2023				570,460,000
Stockholders' equity, balance at end of period at Mar. 31, 2023	$ 14,060		$ 1,056	$ 6	4,493	29,037		(235)	(20,297)
Preferred stock, shares outstanding, balance at beginning of period (in shares) at Dec. 31, 2023	10,700		11,000
Common stock, shares outstanding, balance at beginning of period (in shares) at Dec. 31, 2023				570,838,000
Stockholders' equity, balance at beginning of period at Dec. 31, 2023	$ 14,828		$ 1,056	$ 6	4,553	30,448		(225)	(21,010)
Stockholders' equity, balance at beginning of period (Accounting Standards update 2023-02) at Dec. 31, 2023		$ (37)					$ (37)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	308					308
Other comprehensive loss	(168)							(168)
Purchases of treasury stock	(28)								(28)
Common stock issued under employee benefit plans (in shares)				25,000
Common stock issued under employee benefit plans	3			$ 0	3
Shares Issued, Shares, Share-based Payment Arrangement, after Forfeiture				732,000
Common stock issued and stock-based compensation expense	22			$ 0	22
Dividends — common stock	$ (177)					(177)
Dividends — preferred stock										$ (16)	$ (16)	$ (15)	$ (15)
Preferred stock, shares outstanding, balance at end of period (in shares) at Mar. 31, 2024	10,700		11,000
Common stock, shares outstanding, balance at end of period (in shares) at Mar. 31, 2024				571,595,000
Stockholders' equity, balance at end of period at Mar. 31, 2024	$ 14,720		$ 1,056	$ 6	$ 4,578	$ 30,511		$ (393)	$ (21,038)

Condensed Consolidated Statem_6

Condensed Consolidated Statements of Changes in Stockholders' Equity (Parenthetical) - $ / shares	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Dividends declared, common stock (dollars per share)	$ 0.70	$ 0.60
Series C Preferred Stock [Member]
Dividends declared, preferred stock (dollars per share)	2,750	2,750
Series D Preferred Stock
Dividends declared, preferred stock (dollars per share)	$ 3,062.5	$ 3,062.5

Condensed Consolidated Statem_7

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Cash flows provided by operating activities
Net income	$ 308	$ 968
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for credit losses	1,497	1,102
Deferred income taxes	(199)	(115)
Depreciation and amortization	96	129
Amortization of deferred revenues	(123)	(105)
Net losses on investments and other assets	16	30
Other, net	29	25
Changes in assets and liabilities:
(Increase) decrease in other assets	(246)	133
Increase (decrease) in accrued expenses and other liabilities	465	(376)
Net cash provided by operating activities	1,843	1,791
Cash flows provided by (used for) investing activities
Maturities of available-for-sale investment securities	522	402
Purchases of available-for-sale investment securities	(475)	(285)
Maturities of held-to-maturity investment securities	4	3
Purchases of held-to-maturity investment securities	(12)	(13)
Net change in principal on loans originated for investment	398	(1,245)
Proceeds from the sale of other investments	1	1
Purchases of other investments	(9)	(16)
Purchases of premises and equipment	(71)	(76)
Net cash provided by (used for) investing activities	358	(1,229)
Cash flows provided by (used for) financing activities
Net change in short-term borrowings	(750)	0
Net change in deposits	1,488	4,088
Maturities and repayment of securitized debt	(4)	(1,180)
Maturities and repayments of other long-term borrowings	(1)	(800)
Proceeds from issuance of common stock	3	3
Purchases of treasury stock	(28)	(1,232)
Dividends paid on common and preferred stock	(194)	(175)
Net cash provided by financing activities	514	704
Net increase in cash, cash equivalents and restricted cash	2,715	1,266
Cash, cash equivalents and restricted cash, at the beginning of the period	11,728	8,897
Cash, cash equivalents and restricted cash, at the end of the period	14,443	10,163
Reconciliation of cash, cash equivalents and restricted cash
Cash and cash equivalents	14,004	10,130
Restricted cash	$ 439	$ 33

Background and Basis of Present

Background and Basis of Presentation	3 Months Ended
	Mar. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Background and Basis of Presentation	Background and Basis of Presentation Description of Business Discover Financial Services ("DFS" or the "Company") is a digital banking and payment services company. The Company is a bank holding company under the Bank Holding Company Act of 1956 and a financial holding company under the Gramm-Leach-Bliley Act. Therefore, the Company is subject to oversight, regulation and examination by the Board of Governors of the Federal Reserve System (the "Federal Reserve"). The Company provides digital banking products and services and payment services through its subsidiaries. The Company offers its customers credit card loans, personal loans, home loans and deposit products. The Company also operates the Discover Network, the PULSE network ("PULSE") and Diners Club International ("Diners Club"), collectively known as the Discover Global Network. The Discover Network processes transactions for Discover-branded credit and debit cards and provides payment transaction processing and settlement services. PULSE operates an electronic funds transfer network, providing financial institutions issuing debit cards on the PULSE network with access to automated teller machines ("ATMs") domestically and internationally, as well as merchant acceptance throughout the United States of America ("U.S.") for debit card transactions. Diners Club is a global payments network of licensees, which are generally financial institutions, that issue Diners Club branded credit and charge cards and/or provide card acceptance services. The Company manages its business activities in two segments, Digital Banking and Payment Services, based on the products and services provided. See Note 16: Segment Disclosures for a detailed description of each segment's operations and the allocation conventions used in business segment reporting. In November 2023, the Company announced its Board of Directors had authorized management to explore the sale of its private student loan portfolio. The Company stopped accepting new applications for private student loans February 1, 2024. See "Business — Operating Model — Digital Banking — Private Student Loans" in the Company's annual report on Form 10-K for the year ended December 31, 2023. Pending Merger with Capital One Financial Corporation On February 19, 2024, Discover and Capital One Financial Corporation ("Capital One") jointly announced that they entered into an agreement and plan of merger (the "Merger Agreement"), under which the companies will combine in an all-stock merger, which valued Discover at $35.3 billion based on the price of Capital One common stock on the last trading day before the public announcement of the merger. Under the terms of the Merger Agreement, holders of Discover common stock will receive 1.0192 shares of Capital One common stock for each share of Discover common stock they own. Capital One shareholders will own approximately 60% of the combined company and Discover shareholders will own approximately 40% of the combined company. The Merger Agreement contains customary representations and warranties, covenants and closing conditions. The Board of Directors of the combined company will have fifteen directors, consisting of twelve Capital One Board members and three Discover Board members to be named at a later date. For more information, see Discover’s Current Report on Form 8-K filed with the Securities and Exchange Commission (the "SEC") on February 22, 2024. Completion of the proposed merger remains subject to approval by the Federal Reserve Board and the Office of the Comptroller of the Currency and other customary closing conditions, including the approval of both companies’ shareholders. Basis of Presentation The accompanying condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the U.S. ("GAAP") for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by GAAP for complete consolidated financial statements. In the opinion of management, the financial statements reflect all adjustments necessary for the fair presentation of results for the interim period. All such adjustments are of a normal, recurring nature. The preparation of financial statements in conformity with GAAP requires the Company to make estimates and assumptions that affect the amounts reported in the condensed consolidated financial statements and related disclosures. These estimates are based on information available as of the date of the condensed consolidated financial statements. The Company believes that the estimates used in the preparation of the condensed consolidated financial statements are reasonable. Actual results could differ from these estimates. These interim condensed consolidated financial statements should be read in conjunction with the Company's 2023 audited consolidated financial statements filed with the Company's annual report on Form 10-K for the year ended December 31, 2023. The condensed consolidated financial statements for the three months ended March 31, 2023 have been restated as disclosed in the Company's report on Form 10-Q for the second quarter 2023. Recently Issued Accounting Pronouncements (Not Yet Adopted) In December 2023, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") No. 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures . This ASU enhances the transparency of income tax information through improvements to income tax disclosures primarily related to the rate reconciliation and income taxes paid. Entities are required to disaggregate the rate reconciliation (including percentages and reported amounts) by certain specified categories with additional disaggregation by nature and/or jurisdiction for items over a designated threshold. Income taxes paid (net of refunds received) must be disaggregated by federal, state and foreign taxes and separately by individual jurisdiction in which that amount for a particular jurisdiction is equal to or greater than five percent of total income taxes paid (net of refunds received). This annual disclosure guidance is effective for the Company for the year ending December 31, 2025 and can be adopted on either a prospective or retrospective basis. The Company expects to adopt this standard on a prospective basis. While the ASU implements further income tax disclosure requirements, it does not change how an entity determines its income tax obligation, and it will have no impact on the Company’s consolidated financial condition, results of operations or cash flows. In November 2023, the FASB issued ASU No. 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures . The ASU requires disclosure of additional segment level information, particularly regarding significant segment expenses. Entities must disclose significant expense categories and amounts that are regularly provided to the chief operating decision maker ("CODM") and included in the reported segment measure of profit or loss. Other segment items must also be reported, which are those items that make up the difference between segment revenues less significant segment expenses and reported segment profit or loss. Additionally, entities must disclose the identity of the CODM and how they use the reported measures of segment profit or loss for decision making and assessing segment performance. The guidance is effective for the Company for the year ending December 31, 2024, and interim periods thereafter and requires retrospective application. While the ASU implements further segment disclosure requirements, it does not change how an entity identifies its operating or reportable segments, and it will have no impact on the Company’s consolidated financial condition, results of operations or cash flows. Recently Adopted Accounting Pronouncement In March 2023, the FASB issued ASU No. 2023-02, Investments—Equity Method and Joint Ventures (Topic 323): Accounting for Investments in Tax Credit Structures Using the Proportional Amortization Method . The ASU expanded the use of the proportional amortization method of accounting for tax credit investments. Under the proportional amortization method, the cost of the investment is amortized in proportion to the income tax credits and other income tax benefits received, the net effect of which is recognized as a component of income tax expense on the consolidated statements of income. Previously, the method was limited to Low Income Housing Tax Credit investments, however the Company historically did not elect to use this method. Under the amended guidance, use of proportional amortization is available to any qualifying tax credit investments, which now also includes New Markets Tax Credit investments among others. The ASU was effective for the Company on January 1, 2024. All of the Company's tax credit investments as of January 1, 2024 qualified and are now being accounted for under the proportional amortization method. Upon adoption, the Company recorded a $37 million charge to the opening balance of retained earnings to reflect the cumulative effect of adopting the proportional amortization method on a modified-retrospective basis for the Company's existing tax credit investments. The offset to retained earnings was a decrease of $23 million to the book value of the investments and a $14 million decrease to the related deferred tax asset position. Recognition of proportional amortization as a component of income tax expense rather than pre-tax income will result in an increase in the Company's effective tax rate.

Investments

Investments	3 Months Ended
	Mar. 31, 2024
Investments, Debt and Equity Securities [Abstract]
Investments	Investments The Company's investment securities consist of the following (dollars in millions): March 31, December 31, U.S. Treasury (1) and U.S. GSE (2) securities $ 12,822 $ 12,937 Residential mortgage-backed securities - Agency (3) 700 718 Total investment securities $ 13,522 $ 13,655 (1) Includes $377 million and $320 million of U.S. Treasury securities pledged as swap collateral as of March 31, 2024 and December 31, 2023, respectively. (2) Consists of securities issued by the Federal Home Loan Bank ("FHLB"). (3) Primarily consists of securities issued by Fannie Mae, Freddie Mac, or Ginnie Mae. The amortized cost, gross unrealized gains and losses and fair value of available-for-sale and held-to-maturity investment securities are as follows (dollars in millions): Amortized Gross Gross Fair Value At March 31, 2024 Available-for-Sale Investment Securities (1) U.S. Treasury and U.S. GSE securities $ 12,981 $ 10 $ (169) $ 12,822 Residential mortgage-backed securities - Agency 458 — (19) 439 Total available-for-sale investment securities $ 13,439 $ 10 $ (188) $ 13,261 Held-to-Maturity Investment Securities (2) Residential mortgage-backed securities - Agency (3) $ 261 $ — $ (23) $ 238 Total held-to-maturity investment securities $ 261 $ — $ (23) $ 238 At December 31, 2023 Available-for-Sale Investment Securities (1) U.S. Treasury and U.S. GSE securities $ 12,971 $ 52 $ (86) $ 12,937 Residential mortgage-backed securities - Agency 480 — (15) 465 Total available-for-sale investment securities $ 13,451 $ 52 $ (101) $ 13,402 Held-to-Maturity Investment Securities (2) Residential mortgage-backed securities - Agency (3) $ 253 $ — $ (19) $ 234 Total held-to-maturity investment securities $ 253 $ — $ (19) $ 234 (1) Available-for-sale investment securities are reported at fair value. (2) Held-to-maturity investment securities are reported at amortized cost. (3) Amounts represent residential mortgage-backed securities ("RMBS") that were classified as held-to-maturity as they were entered into as a part of the Company's community reinvestment initiatives. The Company primarily invests in U.S. Treasury obligations and securities issued by a U.S. government agency ("Agency") or government-sponsored enterprise ("U.S. GSE"), which have long histories with no credit losses and are explicitly or implicitly guaranteed by the U.S. federal government. Therefore, management has concluded that there is no expectation of non-payment on its investment securities and does not record an allowance for credit losses on these investments. In addition, the Company does not have the intent to sell any available-for-sale securities in an unrealized loss position and does not believe it is more likely than not that it will be required to sell any such security before recovery of its amortized cost basis. The following table provides information about available-for-sale investment securities with aggregate gross unrealized losses and the length of time that individual investment securities have been in a continuous unrealized loss position (dollars in millions): Number of Securities in a Loss Position Less than 12 months More than 12 months Fair Unrealized Fair Unrealized At March 31, 2024 Available-for-Sale Investment Securities U.S. Treasury and U.S. GSE securities 186 $ 7,701 $ (97) $ 3,532 $ (72) Residential mortgage-backed securities - Agency 31 $ — $ — $ 439 $ (19) At December 31, 2023 Available-for-Sale Investment Securities U.S. Treasury and U.S. GSE securities 105 $ 3,513 $ (13) $ 3,978 $ (73) Residential mortgage-backed securities - Agency 31 $ — $ — $ 465 $ (15) There were no proceeds from sales or recognized gains or losses on available-for-sale securities during the three months ended March 31, 2024 and 2023. See Note 8: Accumulated Other Comprehensive Income for unrealized gains and losses on available-for-sale securities during the three months ended March 31, 2024 and 2023. Maturities of available-for-sale debt securities and held-to-maturity debt securities are provided in the following table (dollars in millions): At March 31, 2024 One Year After One After Five After Ten Total Available-for-Sale Investment Securities — Amortized Cost U.S. Treasury and U.S. GSE securities $ 2,005 $ 10,552 $ 424 $ — $ 12,981 Residential mortgage-backed securities - Agency (1) — 65 24 369 458 Total available-for-sale investment securities $ 2,005 $ 10,617 $ 448 $ 369 $ 13,439 Held-to-Maturity Investment Securities — Amortized Cost Residential mortgage-backed securities - Agency (1) $ — $ — $ — $ 261 $ 261 Total held-to-maturity investment securities $ — $ — $ — $ 261 $ 261 Available-for-Sale Investment Securities — Fair Values U.S. Treasury and U.S. GSE securities $ 1,971 $ 10,428 $ 423 $ — $ 12,822 Residential mortgage-backed securities - Agency (1) — 63 23 353 439 Total available-for-sale investment securities $ 1,971 $ 10,491 $ 446 $ 353 $ 13,261 Held-to-Maturity Investment Securities — Fair Values Residential mortgage-backed securities - Agency (1) $ — $ — $ — $ 238 $ 238 Total held-to-maturity investment securities $ — $ — $ — $ 238 $ 238 (1) Maturities of RMBS are reflective of the contractual maturities of the investment. Other Investments As a part of the Company’s community reinvestment initiatives, the Company has made equity investments in certain limited partnerships and limited liability companies that finance the construction and rehabilitation of affordable rental housing and stimulate economic development in low- to moderate-income communities. These investments are recorded within other assets on the Company’s condensed consolidated statements of financial condition. The Company has elected to account for its qualifying investments in Low Income Housing Tax Credit and New Markets Tax Credit programs under the proportional amortization method beginning January 1, 2024 on a modified retrospective basis. As of March 31, 2024, all of the Company's tax credit investments qualified for this election. Prior to 2024, these investments were accounted for using the equity method. Under the proportional amortization method, the cost of the investment is amortized in proportion to the income tax credits and other income tax benefits received, the net effect of which is recognized as a component of income tax expense on the condensed consolidated statements of income and within cash flows provided by operating activities on the condensed consolidated statements of cash flows. The Company earns a return primarily through tax credits allocated to the affordable housing projects and the community revitalization projects. The Company does not consolidate these investments as the Company does not have a controlling financial interest in the investee entities. The related commitments for future investments are recorded in accrued expenses and other liabilities within the consolidated statements of financial condition for delayed equity contributions that are unconditional and legally binding. Equity contributions that are contingent upon a future event are recognized when that contingent event becomes probable. As of March 31, 2024 and December 31, 2023, the Company had outstanding investments in these entities of $479 million and $514 million, respectively, and related liabilities for delayed equity contributions of $183 million and $187 million, respectively. During the three months ended March 31, 2024, the Company recognized $16 million of amortization and $18 million of income tax credits and other income tax benefits. Non-income tax benefits comprised only immaterial cash distributions from these investments during the three months ended March 31, 2024. The Company holds non-controlling equity positions in several payment services entities and third-party venture capital funds which invest in such entities. Most of the direct investments in such entities are not subject to equity method accounting because the Company does not have significant influence over the investee. The Company's investments in third-party venture capital funds represent limited partnership interests and are accounted for under the equity method. The common or preferred equity securities that the Company holds typically do not have readily determinable fair values. As a result, these investments are carried at cost minus impairment, if any. As of March 31, 2024 and December 31, 2023, the carrying value of these investments, which are recorded within other assets on the Company's condensed consolidated statements of financial condition, was $35 million.

Loan Receivables

Loan Receivables	3 Months Ended
	Mar. 31, 2024
Receivables [Abstract]
Financing Receivables [Text Block]	Loan Receivables The Company has two loan portfolio segments: credit card loans and other loans. The Company's classes of receivables within the two portfolio segments are depicted in the following table (dollars in millions): March 31, December 31, Credit card loans (1)(2) $ 99,475 $ 102,259 Other loans (3) Private student loans (4) 10,480 10,352 Personal loans 10,107 9,852 Other loans 6,493 5,946 Total other loans 27,080 26,150 Total loan receivables 126,555 128,409 Allowance for credit losses (9,258) (9,283) Net loan receivables $ 117,297 $ 119,126 (1) Amounts include carrying values of $13.9 billion and $14.8 billion underlying investors' interest in trust debt at March 31, 2024 and December 31, 2023, respectively, and $15.2 billion and $15.6 billion in seller's interest at March 31, 2024 and December 31, 2023, respectively. See Note 4: Credit Card and Private Student Loan Securitization Activities for additional information. (2) Unbilled accrued interest receivable on credit card loans, which is presented as part of other assets in the Company's condensed consolidated statements of financial condition, was $746 million and $753 million at March 31, 2024 and December 31, 2023, respectively. (3) Accrued interest receivable on private student, personal and other loans, which is presented as part of other assets in the Company's condensed consolidated statements of financial condition, was $555 million, $72 million and $23 million, respectively, at March 31, 2024 and $522 million, $69 million and $21 million, respectively, at December 31, 2023. (4) At March 31, 2024 and December 31, 2023, the private student loan portfolio continued to be classified as held for investment and there were $6.3 billion of private student loans in repayment. Credit Quality Indicators As part of credit risk management activities, on an ongoing basis, the Company reviews information related to the performance of a customer's account with the Company and information from credit bureaus, such as FICO or other credit scores, relating to the customer's broader credit performance. The Company actively monitors key credit quality indicators, including FICO scores and delinquency status, for credit card, private student and personal loans. These indicators are important to understand the overall credit performance of the Company's customers and their ability to repay. FICO scores are generally obtained at the origination of the account and are refreshed monthly or quarterly thereafter to assist in predicting customer behavior. Historically, the Company has noted that accounts with FICO scores below 660 have larger delinquencies and credit losses than those with higher credit scores. The following table provides the distribution of the amortized cost basis (excluding accrued interest receivable presented in other assets) by the most recent FICO scores available for the Company's customers for credit card, private student and personal loan receivables (dollars in millions): Credit Risk Profile by FICO Score March 31, 2024 December 31, 2023 660 and Above Less than 660 660 and Above Less than 660 $ % $ % $ % $ % Credit card loans $ 79,207 80 % $ 20,268 20 % $ 82,238 80 % $ 20,021 20 % Private student loans by origination year (1)(2) 2024 $ 129 98 % $ 3 2 % 2023 1,399 94 % 91 6 % $ 1,010 94 % $ 69 6 % 2022 1,445 94 % 88 6 % 1,495 95 % 85 5 % 2021 1,411 94 % 92 6 % 1,468 94 % 91 6 % 2020 1,127 94 % 76 6 % 1,180 94 % 75 6 % Prior 4,277 93 % 342 7 % 4,537 93 % 342 7 % Total private student loans $ 9,788 93 % $ 692 7 % $ 9,690 94 % $ 662 6 % Personal loans by origination year 2024 $ 1,425 100 % $ 5 — % 2023 4,614 97 % 146 3 % $ 5,149 98 % $ 100 2 % 2022 2,244 92 % 191 8 % 2,604 93 % 187 7 % 2021 869 91 % 85 9 % 1,049 92 % 91 8 % 2020 285 92 % 25 8 % 355 92 % 29 8 % Prior 185 85 % 33 15 % 247 86 % 41 14 % Total personal loans $ 9,622 95 % $ 485 5 % $ 9,404 95 % $ 448 5 % (1) FICO score represents the higher credit score of the cosigner or borrower. Delinquencies are an indicator of credit quality at a point in time. A loan balance is considered delinquent when contractual payments on the loan become 30 days past due. The amortized cost basis (excluding accrued interest receivable presented in other assets) of delinquent loans in the Company's loan portfolio is shown below for credit card, private student and personal loan receivables (dollars in millions): March 31, 2024 December 31, 2023 30-89 Days 90 or Total Past 30-89 Days 90 or Total Past Credit card loans $ 1,869 $ 1,941 $ 3,810 $ 2,038 $ 1,917 $ 3,955 Private student loans by origination year (1) 2024 $ — $ — $ — 2023 2 1 3 $ — $ — $ — 2022 10 6 16 7 2 9 2021 18 10 28 18 6 24 2020 20 10 30 20 7 27 Prior 143 51 194 156 55 211 Total private student loans $ 193 $ 78 $ 271 $ 201 $ 70 $ 271 Personal loans by origination year 2024 $ — $ — $ — 2023 38 12 50 $ 26 $ 8 $ 34 2022 41 15 56 44 16 60 2021 17 6 23 20 8 28 2020 5 2 7 7 2 9 Prior 7 4 11 7 5 12 Total personal loans $ 108 $ 39 $ 147 $ 104 $ 39 $ 143 (1) Private student loans may include a deferment period, during which borrowers are not required to make payments while enrolled in school at least half time as determined by the school. During a deferment period, these loans do not advance into delinquency. Allowance for Credit Losses The following tables provide changes in the Company's allowance for credit losses (dollars in millions): For the Three Months Ended March 31, 2024 Credit Card Loans Private Student Loans Personal Loans Other Loans Total Loans Balance at December 31, 2023 $ 7,619 $ 858 $ 722 $ 84 $ 9,283 Additions Provision for credit losses (1) 1,333 53 134 11 1,531 Deductions Charge-offs (1,649) (47) (113) (3) (1,812) Recoveries 238 5 13 — 256 Net charge-offs (1,411) (42) (100) (3) (1,556) Balance at March 31, 2024 $ 7,541 $ 869 $ 756 $ 92 $ 9,258 For the Three Months Ended March 31, 2023 Credit Card Loans Private Student Loans Personal Loans Other Loans Total Loans Balance at December 31, 2022 $ 5,883 $ 839 $ 595 $ 57 $ 7,374 Cumulative effect of ASU No. 2022-02 adoption (2) (66) — (2) — (68) Balance at January 1, 2023 5,817 839 593 57 7,306 Additions Provision for credit losses (1) 1,002 60 68 5 1,135 Deductions Charge-offs (879) (33) (54) — (966) Recoveries 195 6 15 — 216 Net charge-offs (684) (27) (39) — (750) Balance at March 31, 2023 $ 6,135 $ 872 $ 622 $ 62 $ 7,691 (1) Excludes a $34 million and $33 million adjustment of the liability for expected credit losses on unfunded commitments for the three months ended March 31, 2024 and 2023, respectively, as the liability is recorded in accrued expenses and other liabilities in the Company's condensed consolidated statements of financial condition. (2) Represents the adjustment to the allowance for credit losses as a result of the adoption of ASU No. 2022-02 on January 1, 2023, which eliminated the requirement to apply discounted cash flow measurements for certain troubled debt restructurings. The allowance for credit losses was approximately $9.3 billion at March 31, 2024, which reflects a $25 million release from December 31, 2023. The release in the allowance for credit losses for the three months ended March 31, 2024 was driven by lower receivables and a modestly more favorable economic outlook, offset in part by higher expected delinquencies and losses. The allowance estimation process begins with a loss forecast that uses certain macroeconomic variables and multiple macroeconomic scenarios among its inputs. In estimating the allowance at March 31, 2024, the Company used a macroeconomic forecast that projected the following weighted average amounts: (i) unemployment rate ending 2024 at 4.03% and, within the Company's reasonable and supportable period, peaking at 4.17% in the third quarter of 2025 and (ii) 2.48% growth rate in real gross domestic product in 2024. In estimating expected credit losses, the Company considered the uncertainties associated with borrower behavior and payment trends, as well as recent and expected macroeconomic conditions, including those relating to consumer price inflation and the fiscal and monetary policy responses to that inflation. The Federal Reserve raised its federal funds rate target range substantially during 2022 and the first three quarters of 2023 in an effort to slow economic growth and reduce inflation. Real GDP growth and labor market conditions have exceeded most economists’ expectations, despite an inflation level that has moderated but remains above the target rate. Federal Reserve officials have suggested that the policy rate is likely at its peak for the current tightening cycle, however, the timing and magnitude of rate decreases will be dependent on trends in economic data, particularly inflation. Restrictive monetary policy typically precedes weaker consumer credit conditions caused by rising unemployment as economic growth slows. While credit performance in the Company's lending portfolios has evolved in line with its expectations, the Company assessed the prospects for various macroeconomic outcomes in setting its allowance for credit losses. The forecast period the Company deemed to be reasonable and supportable was 18 months for all periods presented. The 18 months reasonable and supportable forecast period was deemed appropriate given the current economic conditions. For all periods presented, the Company determined that a reversion period of 12 months was appropriate for the same reason. The Company applied a weighted reversion method to provide a more reasonable transition to historical losses for all loan products for all periods presented. The net charge-offs for credit card loans, private student loans and personal loans increased for the three months ended March 31, 2024, when compared to the same periods in 2023, primarily driven by portfolio seasoning. Net charge-offs of principal are recorded against the allowance for credit losses, as shown in the preceding table. Information regarding net charge-offs of interest and fee revenues on credit card and other loans is as follows (dollars in millions): For the Three Months Ended March 31, 2024 2023 Interest and fees accrued subsequently charged-off, net of recoveries (recorded as a reduction of interest income) $ 279 $ 128 Fees accrued subsequently charged-off, net of recoveries (recorded as a reduction to other income) $ 69 $ 41 Gross principal charge-offs of the Company's loan portfolio are presented in the table below, on a year-to-date basis, for credit card, private student and personal loan receivables (dollars in millions): For the Three Months Ended March 31, 2024 2023 Credit card loans $ 1,649 $ 879 Private student loans by origination year 2024 $ — 2023 — $ — 2022 2 — 2021 5 2 2020 6 5 Prior 34 26 Total private student loans $ 47 $ 33 Personal loans by origination year 2024 $ — 2023 28 $ — 2022 48 16 2021 22 18 2020 8 9 Prior 7 11 Total personal loans $ 113 $ 54 Delinquent and Non-Accruing Loans The amortized cost basis (excluding accrued interest receivable presented in other assets) of delinquent and non-accruing loans in the Company's loan portfolio is shown below for each class of loan receivables (dollars in millions): (1) 30-89 Days 90 or Total Past 90 or Total Non-accruing (2) At March 31, 2024 Credit card loans $ 1,869 $ 1,941 $ 3,810 $ 1,900 $ 203 Other loans Private student loans 193 78 271 77 8 Personal loans 108 39 147 37 11 Other loans 33 21 54 3 56 Total other loans 334 138 472 117 75 Total loan receivables $ 2,203 $ 2,079 $ 4,282 $ 2,017 $ 278 At December 31, 2023 Credit card loans $ 2,038 $ 1,917 $ 3,955 $ 1,881 $ 197 Other loans Private student loans 201 70 271 69 8 Personal loans 104 39 143 37 11 Other loans 39 19 58 3 53 Total other loans 344 128 472 109 72 Total loan receivables $ 2,382 $ 2,045 $ 4,427 $ 1,990 $ 269 (1) The payment status of both modified and unmodified loans is included in this table. (2) The Company estimates that the gross interest income that would have been recorded under the original terms of non-accruing credit card loans was $9 million and $8 million for the three months ended March 31, 2024 and 2023, respectively. The Company does not separately track the amount of gross interest income that would have been recorded under the original terms of loans. Instead, the Company estimated this amount based on customers' current balances and most recent interest rates. Loan Modifications to Borrowers Experiencing Financial Difficulty The Company has internal loan modification programs that provide relief to credit card, private student and personal loan borrowers who are experiencing financial hardship. The internal loan modification programs include both temporary and permanent programs, which vary by product. External loan modification programs, through third party consumer credit counseling agencies, are also available for credit card and personal loans. Those programs feature interest rate reductions, payment delays, term extensions, or a combination thereof. For credit card customers, the Company offers both temporary and permanent hardship programs. The temporary hardship programs consist of an interest rate reduction lasting for a period no longer than 12 months. Charging privileges on these accounts are generally suspended while in the program. However, if the customer meets certain criteria, charging privileges may be reinstated following completion of the program. The permanent modification program involves closing the account, changing the structure of the loan to a fixed payment loan with a maturity no longer than 72 months and reducing the interest rate on the loan. The permanent modification program does not typically provide for the forgiveness of unpaid principal, but may allow for the reversal of certain unpaid interest or fee assessments. The Company also makes permanent loan modifications for customers who request financial assistance through external sources, such as a consumer credit counseling agency program. These loans typically receive a reduced interest rate, typically continue to be subject to the original minimum payment terms and do not normally include waiver of unpaid principal, interest or fees. To assist private student loan borrowers who are experiencing temporary financial difficulties but are willing to resume making payments, the Company has offered a payment delay (in the form of hardship forbearance or temporary payment reduction), or a payment delay (in the form of a temporary payment reduction) combined with a temporary interest rate reduction. These programs are offered up to six consecutive months at one time. Hardship forbearance is limited to a lifetime usage cap of 12 months. Beginning in the fourth quarter of 2023, the lifetime usage cap of certain other programs was increased from 12 to 36 months. For personal loan customers, the Company offers various payment programs, including temporary and permanent programs, in certain situations. The temporary programs normally consist of reducing the minimum payment for no longer than 12 months and, in certain circumstances, the interest rate on the loan is reduced. The permanent programs involve extending the loan term and, in certain circumstances, reducing the interest rate on the loan. The total term of the loan, including modification, may not exceed nine years. The Company also allows permanent loan modifications for customers who request financial assistance through external sources, similar to the credit card customers discussed above. Payments are modified based on the new terms agreed upon with the credit counseling agency. In addition to the programs described above, the Company will in certain cases accept partial payment in full satisfaction of the outstanding receivable. This is a form of principal forgiveness also known as a settlement. The difference between the loan balance and the amount received at settlement is recorded as a charge-off. The Company monitors borrower performance after using payment programs or forbearance. The Company believes the programs are useful in assisting customers experiencing financial difficulties and allowing them to make timely payments. In addition to helping customers with their credit needs, these programs are designed to maximize collections and ultimately the Company’s profitability. The Company plans to continue to use payment programs to provide relief to customers experiencing financial difficulties. The following table provides the period-end amortized cost basis, by modification category, of loans to borrowers experiencing financial difficulty that entered a modification program during the period (dollars in millions). Some of the loans presented in the table below may no longer be enrolled in a program at period-end: For the Three Months Ended March 31, 2024 2023 Credit card loans (1)(2) Interest rate reduction $ 920 $ 632 Total credit card loans (3) $ 920 $ 632 % of total class of financing receivables 0.92 % 0.70 % Private student loans (1) Payment delay (4) $ 1 $ 3 Interest rate reduction and payment delay (4) 101 29 Total private student loans (3) $ 102 $ 32 % of total class of financing receivables 0.97 % 0.04 % Personal loans (1) Payment delay (4) $ 4 $ 2 Term extension (5) 10 8 Interest rate reduction and payment delay (4) 26 14 Interest rate reduction and term extension (5) 14 6 Total personal loans (3) $ 54 $ 30 % of total class of financing receivables 0.53 % 0.36 % (1) Accrued interest receivable (including unbilled accrued interest receivable for credit card loans) on modified loans to borrowers experiencing financial difficulty, which is presented as part of other assets in the Company's condensed consolidated statements of financial condition, was immaterial at March 31, 2024 and 2023. (2) Accounts that entered a credit card loan modification program include $185 million and $118 million that were converted from revolving line-of-credit arrangements to term loans during the three months ended March 31, 2024 and 2023, respectively. (3) For settlements, the amortized cost basis is zero at period-end and therefore there is no amount reported for principal forgiveness in the table above. See financial effects table below for principal forgiveness to borrowers experiencing financial difficulty. (4) The Company defines a payment delay as a temporary reduction in payments below the original contractually required payment amounts (e.g., interest only payments). The Company's credit card loan modification programs do not result in an other than insignificant delay in payment. (5) The Company defines term extensions as only those modifications for which the maturity date is extended beyond the original contractual maturity date by virtue of a change in terms other than a payment delay as defined above. Modifications to credit card loans are not considered term extensions because credit card loans do not have a fixed repayment term. The only non-cancellable commitments the Company has to lend additional funds to borrowers experiencing financial difficulty relate to certain private student loans. As of March 31, 2024, the amount of such commitments associated with loans modified during the periods presented was immaterial. The following table provides information on the financial effects of loan modifications to borrowers experiencing financial difficulty, by modification type, made during the period (dollars in millions): For the Three Months Ended March 31, 2024 2023 Credit card loans Weighted-average interest rate reduction 14.42 % 13.38 % Principal forgiven $ 56 NM Interest and fees forgiven (1) $ 56 $ 12 Private student loans Weighted-average interest rate reduction 8.84 % 8.02 % Payment delay duration (in months) (2) 6 to 12 6 to 12 Personal loans Weighted-average interest rate reduction 13.20 % 11.55 % Weighted-average term extension (in months) 40 38 Payment delay duration (in months) (2) 6 to 12 6 to 12 (1) Represents the amount of interest and fees forgiven resulting from accounts entering into a credit card loan modification program and pre-charge off settlements. Interest and fees forgiven are reversed against the respective line items in the condensed consolidated statements of income. (2) For private student loan payment delays, the Company offers up to six consecutive months of delay and limits assistance to a life of loan maximum of 36 months. For personal loan payment delays, the Company limits this assistance to a life of loan maximum of 12 months. Loan receivables that have been modified are subject to the same requirements for the accrual of expected credit loss over their expected remaining lives as for unmodified loans. The allowance for credit losses incorporates modeling of historical loss data and thereby captures the higher risk associated with modified loans to borrowers experiencing financial difficulty based on their account attributes. The following table presents the payment status and period-end amortized cost basis, by class of loan receivable, of loans that were modified to borrowers experiencing financial difficulty during the 12 months preceding each of the periods presented (dollars in millions) (1) : Current 30-89 Days 90 or At March 31, 2024 Credit card loans $ 2,118 $ 257 $ 217 Private student loans 207 22 8 Personal loans 126 23 4 Total $ 2,451 $ 302 $ 229 At December 31, 2023 Credit card loans $ 1,882 $ 252 $ 196 Private student loans 147 18 8 Personal loans 109 20 4 Total $ 2,138 $ 290 $ 208 (1) This table includes any loan that entered a modification program during the preceding 12 months without regard to whether it remained in a modification program as of the reporting date. The following table presents the defaulted amount and period-end amortized cost basis, by modification category, of loans that defaulted during the period and were modified to borrowers experiencing financial difficulty during the 12 months preceding default (dollars in millions): For the Three Months Ended March 31, 2024 Defaulted Amount (1) Period-end Amortized Cost Basis Credit card loans Interest rate reduction $ 205 $ 161 Total credit card loans $ 205 $ 161 Private student loans Payment delay $ 2 $ 2 Interest rate reduction and payment delay 17 16 Total private student loans $ 19 $ 18 Personal loans Payment delay $ 1 $ 1 Term extension 2 1 Interest rate reduction and payment delay 7 3 Interest rate reduction and term extension 4 3 Total personal loans $ 14 $ 8 (1) For purposes of this disclosure, a loan is considered to be defaulted when it is 60 days or more delinquent at month end and has advanced two stages of delinquency subsequent to modification. Loans that entered a modification program in any stage of delinquency but did not experience a further payment default are included in the payment status table above but are not counted as defaulted for purposes of this disclosure. The defaulted amount and period-end amortized cost basis of loans modified on or after January 1, 2023 to borrowers experiencing financial difficulty which subsequently defaulted was immaterial for the three months ended March 31, 2023, for all classes of loan receivables.

Credit Card and Private Student

Credit Card and Private Student Loan Securitization Activities	3 Months Ended
	Mar. 31, 2024
Variable Interest Entities Disclosure [Abstract]
Credit Card and Private Student Loan Securitization Activities	Credit Card and Private Student Loan Securitization Activities The Company's securitizations are accounted for as secured borrowings and the related trusts are treated as consolidated subsidiaries of the Company. For a description of the Company's principles of consolidation with respect to VIEs, see Note 1: Background and Basis of Presentation to the consolidated financial statements in the Company's annual report on Form 10-K for the year ended December 31, 2023. Credit Card Securitization Activities The Company accesses the term asset securitization market through Discover Card Master Trust I ("DCMT") and Discover Card Execution Note Trust ("DCENT"). Credit card loan receivables are transferred into DCMT and beneficial interests in DCMT are transferred into DCENT. DCENT issues debt securities to investors that are reported primarily in long-term borrowings. The DCENT debt structure consists of four classes of securities (DiscoverSeries Class A, B, C and D notes), with the most senior class generally receiving a triple-A rating. To issue senior, higher-rated classes of notes, it is necessary to obtain the appropriate amount of credit enhancement, generally through the issuance of junior, lower-rated or more highly subordinated classes of notes. Wholly-owned subsidiaries of Discover Bank hold the subordinated classes of notes. The Company is exposed to credit risk associated with trust receivables as of the balance sheet date through the retention of these subordinated interests. The estimate of expected credit losses on trust receivables is included in the allowance for credit losses estimate. The Company's retained interests in the trust's assets, consisting of investments in DCENT notes held by subsidiaries of Discover Bank, constitute intercompany positions that are eliminated in the preparation of the Company's condensed consolidated statements of financial condition. Upon transfer of credit card loan receivables to the trust, the receivables and certain cash flows derived from them become restricted for use in meeting obligations to the trust's creditors. Further, the transferred credit card loan receivables are owned by the trust and are not available to the Company's third-party creditors. The trusts have ownership of cash balances, the amounts of which are reported in restricted cash within the Company's condensed consolidated statements of financial condition. Except for the seller's interest in trust receivables, the Company's interests in trust assets are generally subordinate to the interests of third-party investors in trust debt and, as such, may not be realized by the Company if needed to absorb deficiencies in cash flows that are allocated to those investors. Apart from the restricted assets related to securitization activities, the investors and the securitization trusts have no recourse to the Company's other assets or the Company's general credit for a shortage in cash flows. The carrying values of these restricted assets, which are presented on the Company's condensed consolidated statements of financial condition as relating to securitization activities, are shown in the following table (dollars in millions): March 31, December 31, Restricted cash $ 432 $ 36 Investors' interests held by third-party investors 10,975 11,725 Investors' interests held by wholly-owned subsidiaries of Discover Bank 2,917 3,117 Seller's interest 15,155 15,598 Loan receivables (1) 29,047 30,440 Allowance for credit losses allocated to securitized loan receivables (1) (1,323) (1,347) Net loan receivables 27,724 29,093 Other assets 3 2 Carrying value of assets of consolidated variable interest entities $ 28,159 $ 29,131 (1) The Company maintains its allowance for credit losses at an amount equal to lifetime expected credit losses associated with all loan receivables, which includes all loan receivables in the trusts. Therefore, the credit risk associated with the transferred receivables is fully reflected on the Company's statements of financial condition in accordance with GAAP. The debt securities issued by the consolidated trusts are subject to credit, payment and interest rate risks on the transferred credit card loan receivables. To protect investors in the securities, there are certain features or triggering events that will cause an early amortization of the debt securities, including triggers related to the impact of the performance of the trust receivables on the availability and adequacy of cash flows to meet contractual requirements. As of March 31, 2024, no economic or other early amortization events have occurred. The Company continues to own and service the accounts that generate the loan receivables held by the trusts. Discover Bank receives servicing fees from the trusts based on a percentage of the monthly investor principal balance outstanding. Although the fee income to Discover Bank offsets the fee expense to the trusts and thus is eliminated in consolidation, failure to service the transferred loan receivables in accordance with contractual requirements could lead to a termination of the servicing rights and the loss of future servicing income, net of related expenses. Private Student Loan Securitization Activities The Company's private student loan trust receivables reported in loan receivables and the related debt issued by the trust reported in long-term borrowings were immaterial as of March 31, 2024 and December 31, 2023. The amounts are included, together with amounts related to the Company's credit card securitizations, in the supplemental information about assets and liabilities of consolidated variable interest entities, which is presented with the Company's condensed consolidated statements of financial condition.

Deposits

Deposits	3 Months Ended
	Mar. 31, 2024
Deposits [Abstract]
Deposits	Deposits The Company obtains deposits from consumers directly or through affinity relationships ("direct-to-consumer deposits"). Additionally, the Company obtains deposits through third-party securities brokerage firms that offer the Company's deposits to their customers ("brokered deposits"). Direct-to-consumer deposit products include savings accounts, certificates of deposit, money market accounts, IRA savings accounts, IRA certificates of deposit and checking accounts. Brokered deposit products include certificates of deposit and sweep accounts. The following table summarizes certificates of deposits maturing over the remainder of this year, over each of the next four years and thereafter (dollars in millions): At March 31, 2024 2024 $ 21,263 2025 12,190 2026 4,211 2027 4,408 2028 2,161 Thereafter 1,009 Total $ 45,242

Long-Term Borrowings

Long-Term Borrowings	3 Months Ended
	Mar. 31, 2024
Debt Disclosure [Abstract]
Long-Term Borrowings	Long-Term Borrowings Long-term borrowings consist of borrowings having original maturities of one year or more. The following table provides a summary of the Company's long-term borrowings and weighted-average interest rates on outstanding balances (dollars in millions): March 31, 2024 December 31, 2023 Maturity Interest Weighted-Average Interest Rate Outstanding Amount Outstanding Amount Securitized Debt Fixed-rate asset-backed securities (1) 2024-2026 0.58% - 5.03% 3.17% $ 9,947 $ 10,003 Floating-rate asset-backed securities (2) 2024 6.04% 6.04% 925 925 Total Discover Card Master Trust I and Discover Card Execution Note Trust 10,872 10,928 Floating-rate asset-backed security (3)(4) 2031 9.50% 9.50% 61 65 Total private student loan securitization trust 61 65 Total long-term borrowings - owed to securitization investors 10,933 10,993 Discover Financial Services (Parent Company) Fixed-rate senior notes 2024-2032 3.75% - 6.70% 4.68% 3,337 3,336 Fixed-rate retail notes 2025-2031 3.25% - 4.40% 3.82% 139 140 Fixed to floating-rate senior notes (5) 2034 7.96% 7.96% 992 993 Discover Bank Fixed-rate senior bank notes (1) 2024-2030 2.45% - 4.65% 3.53% 3,535 3,571 Fixed-rate subordinated bank notes 2028 5.97% 5.97% 491 500 Fixed-rate Federal Home Loan Bank advances 2030 4.77% - 4.82% 4.82% 523 523 Floating-rate Federal Home Loan Bank advances (6) 2024 5.49% - 5.59% 5.59% 525 525 Total long-term borrowings $ 20,475 $ 20,581 (1) The Company uses interest rate swaps to hedge portions of these long-term borrowings against changes in fair value attributable to changes in the applicable benchmark interest rates. The use of these interest rate swaps impacts the carrying value of the debt. See Note 15: Derivatives and Hedging Activities. (2) DCENT floating-rate asset-backed securities include issuances with the following interest rate terms: 1-month Term SOFR + 0.11448% Tenor Spread Adjustment + 60 basis points as of March 31, 2024. (3) The private student loan securitization trust floating-rate asset-backed security includes an issuance with the following interest rate term: Prime rate + 100 basis points as of March 31, 2024. (4) Repayment of this debt is dependent upon the timing of principal and interest payments on the underlying private student loans. The date shown represents the final maturity date. (5) The fixed to floating-rate senior notes include a rate reset on November 2, 2033, to a floating rate based on compounded SOFR + 3.370%. (6) The floating-rate FHLB advances include interest rate terms based on SOFR plus a spread ranging from 16 to 26 basis points as of March 31, 2024. The following table summarizes long-term borrowings maturing over the remainder of this year, over each of the next four years and thereafter (dollars in millions): March 31, 2024 2024 $ 4,250 2025 6,121 2026 4,868 2027 1,001 2028 1,412 Thereafter 2,823 Total $ 20,475 As a member of the FHLB of Chicago, the Company has access to both short- and long-term advance structures with maturities ranging from overnight to 30 years. As of March 31, 2024, the Company had total committed borrowing capacity of $4.1 billion based on the amount and type of assets pledged, of which the outstanding balance was comprised of $1.0 billion in long-term advances. As of December 31, 2023, the Company had total committed borrowing capacity of $3.6 billion based on the amount and type of assets pledged, of which the outstanding balance was comprised of $1.0 billion in long-term advances. These advances are presented as short- or long-term borrowings on the condensed consolidated statements of financial condition based on the contractual maturity at origination. Additionally, the Company has access to committed borrowing capacity through private securitizations to support the funding of its credit card loan receivables. As of March 31, 2024, the total commitment of secured credit facilities through private providers was $3.5 billion, none of which was drawn. As of December 31, 2023, the total commitment of secured credit facilities through private providers was $3.5 billion, $750 million of which was outstanding as a short-term advance. This advance is presented as short-term borrowings on the condensed consolidated statements of financial condition. Access to the unused portions of the secured credit facilities is subject to the terms of the agreements with each of the providers. The secured credit facilities have various expirations in 2025. Borrowings outstanding under each facility bear interest at a margin above the Term Secured Overnight Financing Rate ("SOFR") or the asset-backed commercial paper costs of each provider. The terms of each agreement provide for a commitment fee to be paid on the unused capacity and include various affirmative and negative covenants, including performance metrics and legal requirements similar to those required to issue any term securitization transaction.

Preferred Stock (Notes)

Preferred Stock (Notes)	3 Months Ended
	Mar. 31, 2024
Equity [Abstract]
Preferred Stock	Preferred Stock The table below presents a summary of the Company's non-cumulative perpetual preferred stock that is outstanding at March 31, 2024 (dollars in millions, except per depositary share amounts): Series Description Initial Issuance Date Liquidation Preference and Redemption Price per Depositary Share (1) Per Annum Dividend Rate in effect at March 31, 2024 Total Depositary Shares Authorized, Issued and Outstanding Carrying Value March 31, 2024 December 31, 2023 March 31, 2024 December 31, 2023 C (2)(3)(4) Fixed-to-Floating Rate 10/31/2017 $ 1,000 5.500 % 570,000 570,000 $ 563 $ 563 D (2)(5)(6) Fixed-Rate Reset 6/22/2020 $ 1,000 6.125 % 500,000 500,000 493 493 Total Preferred Stock 1,070,000 1,070,000 $ 1,056 $ 1,056 (1) Redeemable at the redemption price plus declared and unpaid dividends. (2) Issued as depositary shares, each representing 1/100 th interest in a share of the corresponding series of preferred stock. Each preferred share has a par value of $0.01. (3) Redeemable at the Company’s option, subject to regulatory approval, either (i) in whole or in part on any dividend payment date on or after October 30, 2027, or (ii) in whole but not in part, at any time within 90 days following a regulatory capital treatment event (as defined in the certificate of designations for the Series C preferred stock). (4) Any dividends declared are payable semi-annually in arrears at a rate of 5.500% per annum until October 30, 2027. Thereafter, dividends declared will be payable quarterly in arrears at a floating rate equal to 3-month Term SOFR plus a spread of 3.338% per annum. (5) Redeemable at the Company’s option, subject to regulatory approval, either (i) in whole or in part during the three-month period prior to, and including, each reset date (as defined in the certificate of designations for the Series D preferred stock) or (ii) in whole but not in part, at any time within 90 days following a regulatory capital treatment event (as defined in the certificate of designations for the Series D Preferred Stock). (6) Any dividends declared are payable semi-annually in arrears at a rate of 6.125% per annum until September 23, 2025, after which the dividend rate will reset every 5 years to a fixed annual rate equal to the 5-year Treasury plus a spread of 5.783%.

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income	3 Months Ended
	Mar. 31, 2024
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Accumulated Other Comprehensive Income	Accumulated Other Comprehensive Income Changes in each component of accumulated other comprehensive (loss) income ("AOCI") were as follows (dollars in millions): Unrealized (Losses) Gains on Available-for-Sale Investment Securities, Net of Tax (Losses) Gains on Cash Flow Hedges, Net of Tax Losses on Pension Plan, Net of Tax AOCI For the Three Months Ended March 31, 2024 Balance at December 31, 2023 $ (37) $ (8) $ (180) $ (225) Net change (97) (71) — (168) Balance at March 31, 2024 $ (134) $ (79) $ (180) $ (393) For the Three Months Ended March 31, 2023 Balance at December 31, 2022 $ (136) $ (14) $ (189) $ (339) Net change 92 12 — 104 Balance at March 31, 2023 $ (44) $ (2) $ (189) $ (235) The following table presents each component of other comprehensive income ("OCI") before reclassifications and amounts reclassified from AOCI for each component of OCI before- and after-tax (dollars in millions): Before Tax Tax Benefit (Expense) Net of Tax For the Three Months Ended March 31, 2024 Available-for-Sale Investment Securities Net unrealized holding losses arising during the period $ (129) $ 32 $ (97) Net change $ (129) $ 32 $ (97) Cash Flow Hedges Net unrealized losses arising during the period $ (131) $ 32 $ (99) Amounts reclassified from AOCI 37 (9) 28 Net change $ (94) $ 23 $ (71) For the Three Months Ended March 31, 2023 Available-for-Sale Investment Securities Net unrealized holding gains arising during the period $ 122 $ (30) $ 92 Net change $ 122 $ (30) $ 92 Cash Flow Hedges Net unrealized gains arising during the period $ 10 $ (2) $ 8 Amounts reclassified from AOCI 5 (1) 4 Net change $ 15 $ (3) $ 12

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2024
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The following table presents the calculation of the Company's effective income tax rate (dollars in millions): For the Three Months Ended March 31, 2024 2023 Income before income taxes $ 404 $ 1,257 Income tax expense $ 96 $ 289 Effective income tax rate 23.7 % 23.0 % The effective tax rate increased for the three months ended March 31, 2024, as compared to the same period in 2023, due to the adoption of the proportional amortization method for qualifying tax credit investments effective January 1, 2024, offset by the decrease in pretax income. The Company is subject to examination by the Internal Revenue Service and tax authorities in various state, local and foreign tax jurisdictions. The Company's federal income tax filings are open to examinations for the tax years ended December 31, 2020 and forward. The Company regularly assesses the likelihood of additional assessments or settlements in each of the taxing jurisdictions. At this time, the potential change in unrecognized tax benefits is expected to be immaterial over the next 12 months. The Company believes that its reserves are sufficient to cover any tax, penalties and interest that would result from such examinations.

Earnings Per Share

Earnings Per Share	3 Months Ended
	Mar. 31, 2024
Earnings Per Share [Abstract]
Earnings Per Share	Earnings Per Share The following table presents the calculation of basic and diluted earnings per share ("EPS") (dollars and shares in millions, except per share amounts): For the Three Months Ended March 31, 2024 2023 Numerator Net income $ 308 $ 968 Preferred stock dividends (31) (31) Net income available to common stockholders 277 937 Income allocated to participating securities (3) (6) Net income allocated to common stockholders $ 274 $ 931 Denominator Weighted-average shares of common stock outstanding 250 262 Weighted-average shares of common stock outstanding and common stock equivalents 250 262 Basic earnings per common share $ 1.10 $ 3.55 Diluted earnings per common share $ 1.10 $ 3.55 Anti-dilutive securities were not material and had no impact on the computation of diluted EPS for the three months ended March 31, 2024 and 2023.

Capital Adequacy

Capital Adequacy	3 Months Ended
	Mar. 31, 2024
Broker-Dealer, Net Capital Requirement, SEC Regulation [Abstract]
Capital Adequacy	Capital Adequacy DFS is subject to the capital adequacy guidelines of the Federal Reserve. Discover Bank, the Company's banking subsidiary, is subject to various regulatory capital requirements as administered by the FDIC. Failure to meet minimum capital requirements can result in the initiation of certain mandatory and possibly additional discretionary actions by regulators that, if undertaken, could limit the Company's business activities and have a direct material effect on the financial condition and operating results of DFS and Discover Bank. Under capital adequacy guidelines and the regulatory framework for prompt corrective action, DFS and Discover Bank must meet specific risk-based capital requirements and leverage ratios that involve quantitative measures of assets, liabilities and certain off-balance sheet items, as calculated under regulatory guidelines. Capital amounts and classification are also subject to qualitative judgments by the regulators about components, risk weightings and other factors. DFS and Discover Bank are subject to regulatory and capital rules issued by the Federal Reserve and FDIC, respectively, under the Basel Committee's December 2010 framework ("Basel III rules"). Under the Basel III rules, DFS and Discover Bank are classified as "standardized approach" entities. Standardized approach entities are defined as U.S. banking organizations with consolidated total assets over $50 billion but not exceeding $250 billion and consolidated total on-balance sheet foreign exposure less than $10 billion. In accordance with the final rule on the impact of current expected credit losses ("CECL") on regulatory capital, the Company has elected to phase in the impact over three years beginning in 2022. Accordingly, the Company's Common Equity Tier 1 ("CET1") capital ratios are higher than they otherwise would have been. The Company's CET1 capital ratios will continue to be favorably impacted by this election over the phase-in period, which ends December 31, 2024. As of March 31, 2024 and December 31, 2023, DFS and Discover Bank met all Basel III minimum capital ratio requirements to which they were subject. DFS and Discover Bank also met the requirements to be considered "well-capitalized" under Regulation Y and prompt corrective action rules, respectively. There have been no conditions or events that management believes have changed DFS' or Discover Bank's category. To be categorized as "well-capitalized", DFS and Discover Bank must maintain minimum capital ratios outlined in the table below. The following table shows the actual capital amounts and ratios of DFS and Discover Bank and comparisons of each to the regulatory minimum and "well-capitalized" requirements (dollars in millions): Actual Minimum Capital Capital Requirements Amount Ratio (1) Amount Ratio Amount (2) Ratio (2) March 31, 2024 Total capital (to risk-weighted assets) Discover Financial Services $ 17,513 13.3 % $ 10,499 ≥8.0% $ 13,124 ≥10.0% Discover Bank $ 16,598 12.8 % $ 10,349 ≥8.0% $ 12,936 ≥10.0% Tier 1 capital (to risk-weighted assets) Discover Financial Services $ 15,394 11.7 % $ 7,874 ≥6.0% $ 7,874 ≥6.0% Discover Bank $ 13,752 10.6 % $ 7,762 ≥6.0% $ 10,349 ≥8.0% Tier 1 capital (to average assets) Discover Financial Services $ 15,394 10.1 % $ 6,086 ≥4.0% N/A N/A Discover Bank $ 13,752 9.2 % $ 6,004 ≥4.0% $ 7,505 ≥5.0% Common Equity Tier 1 (to risk-weighted assets) Discover Financial Services $ 14,338 10.9 % $ 5,906 ≥4.5% N/A N/A Discover Bank $ 13,752 10.6 % $ 5,821 ≥4.5% $ 8,409 ≥6.5% December 31, 2023 Total capital (to risk-weighted assets) Discover Financial Services $ 17,986 13.7 % $ 10,471 ≥8.0% $ 13,088 ≥10.0% Discover Bank $ 16,856 13.0 % $ 10,352 ≥8.0% $ 12,939 ≥10.0% Tier 1 capital (to risk-weighted assets) Discover Financial Services $ 15,872 12.1 % $ 7,853 ≥6.0% $ 7,853 ≥6.0% Discover Bank $ 13,910 10.8 % $ 7,764 ≥6.0% $ 10,352 ≥8.0% Tier 1 capital (to average assets) Discover Financial Services $ 15,872 10.7 % $ 5,915 ≥4.0% N/A N/A Discover Bank $ 13,910 9.5 % $ 5,833 ≥4.0% $ 7,292 ≥5.0% Common Equity Tier 1 (to risk-weighted assets) Discover Financial Services $ 14,816 11.3 % $ 5,890 ≥4.5% N/A N/A Discover Bank $ 13,910 10.8 % $ 5,823 ≥4.5% $ 8,411 ≥6.5% (1) Capital ratios are calculated based on the Basel III standardized approach rules, subject to applicable transition provisions, including CECL transition provisions. (2) The Basel III rules do not establish well-capitalized thresholds for these measures for bank holding companies. Existing well-capitalized thresholds established in the Federal Reserve's Regulation Y have been included where available.

Commitments, Contingencies and

Commitments, Contingencies and Guarantees	3 Months Ended
	Mar. 31, 2024
Commitments Contingencies and Guarantees [Abstract]
Commitments, Contingencies and Guarantees	Commitments, Contingencies and Guarantees In the normal course of business, the Company enters into a number of off-balance sheet commitments, transactions and obligations under guarantee arrangements that expose the Company to varying degrees of risk. The Company's commitments, contingencies and guarantee relationships are described below. Commitments Unused Credit Arrangements At March 31, 2024, the Company had unused credit arrangements for loans of approximately $233.0 billion. Such arrangements arise primarily from agreements with customers for unused lines of credit on certain credit cards and certain other loan products, provided there is no violation of conditions in the related agreements. These arrangements, substantially all of which the Company can terminate at any time and which do not necessarily represent future cash requirements, are periodically reviewed based on account usage, customer creditworthiness, loan qualification and the cost of capital. As the Company’s credit card loans are unconditionally cancellable, no liability for expected credit losses is required for unused lines of credit. For all other loans, the Company records a liability for expected credit losses for unfunded commitments, which is presented as part of accrued expenses and other liabilities in the condensed consolidated statements of financial condition. Contingencies See Note 13: Litigation and Regulatory Matters for a description of potential liability arising from pending litigation or regulatory proceedings involving the Company. Guarantees The Company has obligations under certain guarantee arrangements, including contracts, indemnification agreements and representations and warranties, which contingently require the Company to make payments to the guaranteed party based on changes in an underlying asset, liability or equity security of a guaranteed party, rate or index. Also included as guarantees are contracts that contingently require the Company to make payments to a guaranteed party based on another entity's failure to perform under an agreement. The Company's use of guarantees is disclosed below by type of guarantee. Securitizations Representations and Warranties As part of the Company's financing activities, the Company provides representations and warranties that certain assets pledged as collateral in secured borrowing arrangements conform to specified guidelines. Due diligence is performed by the Company, which is intended to ensure that asset guideline qualifications are met. If the assets pledged as collateral do not meet certain conforming guidelines, the Company may be required to replace, repurchase or sell such assets. In its credit card securitization activities, the Company would replace nonconforming receivables through the allocation of excess seller's interest or from additional transfers from the unrestricted pool of receivables. If the Company could not add enough receivables to satisfy the requirement, an early amortization (or repayment) of investors' interests would be triggered. In its student loan securitizations, the Company would generally repurchase the loans from the trust at the outstanding principal amount plus interest. The maximum potential amount of future payments the Company could be required to make would be equal to the current outstanding balances of third-party investor interests in credit card asset-backed securities and the principal amount of any private student loan secured borrowings, plus any unpaid interest for the corresponding secured borrowings. The Company has recorded substantially all of the maximum potential amount of future payments in long-term borrowings on the Company's condensed consolidated statements of financial condition. The Company has not recorded any incremental contingent liability associated with its secured borrowing representations and warranties. Management believes that the probability of having to replace, repurchase or sell assets pledged as collateral under secured borrowing arrangements, including an early amortization event, is low. Counterparty Settlement Guarantees Diners Club and DFS Services LLC (on behalf of PULSE) have various counterparty exposures, which are listed below: • Merchant Guarantee . Diners Club has entered into contractual relationships with certain international merchants, which generally include travel-related businesses, for the benefit of all Diners Club licensees. The licensees hold the primary liability to settle the transactions of their customers with these merchants. However, Diners Club retains a counterparty exposure if a licensee fails to meet its financial payment obligation to one of these merchants. • ATM Guarantee. PULSE entered into contractual relationships with certain international ATM acquirers in which DFS Services LLC retains counterparty exposure if an issuer fails to fulfill its settlement obligation. • Global Network Alliance Guarantee . Discover Network, Diners Club and PULSE have entered into contractual relationships with certain international payment networks in which DFS Services LLC retains the counterparty exposure if a network fails to fulfill its settlement obligation. The maximum potential amount of future payments related to such contingent obligations is dependent upon the transaction volume processed between the time a potential counterparty defaults on its settlement and the time at which the Company disables the settlement of any further transactions for the defaulting party. The Company has some contractual remedies to offset these counterparty settlement exposures (such as letters of credit or pledged deposits), however, there is no limitation on the maximum amount the Company may be liable to pay. The actual amount of the potential exposure cannot be quantified as the Company cannot determine whether particular counterparties will fail to meet their settlement obligations. In the event all licensees and/or issuers were to become unable to settle their transactions, the Company estimates its maximum potential counterparty exposures to these settlement guarantees would be approximately $110 million as of March 31, 2024. The Company believes that the estimated amounts of maximum potential future payments are not representative of the Company's actual potential loss exposure given Diners Club's and PULSE's insignificant historical losses from these counterparty exposures. As of March 31, 2024, the Company had not recorded any contingent liability in the condensed consolidated statements of financial condition for these counterparty exposures and management believes that the probability of any payments under these arrangements is low. Discover Network Merchant Chargeback Guarantees The Company operates the Discover Network, issues payment cards and permits third parties to issue payment cards. The Company is contingently liable for certain transactions processed on the Discover Network in the event of a dispute between the payment card customer and a merchant. The contingent liability arises if the disputed transaction involves a merchant or merchant acquirer with whom the Discover Network has a direct relationship. If a dispute is resolved in the customer's favor, the Discover Network will credit or refund the disputed amount to the Discover Network card issuer, who in turn credits its customer's account. The Discover Network will then charge back the disputed amount of the payment card transaction to the merchant or merchant acquirer, where permitted by the applicable agreement, to seek recovery of amounts already paid to the merchant for payment card transactions. If the Discover Network is unable to collect the amount subject to dispute from the merchant or merchant acquirer (e.g., in the event of merchant default or dissolution or after expiration of the time period for chargebacks in the applicable agreement), the Discover Network will bear the loss for the amount credited or refunded to the customer. In most instances, a loss by the Discover Network is unlikely to arise in connection with payments on card transactions because most products or services are delivered when purchased and credits are issued by merchants on returned items in a timely fashion, thus minimizing the likelihood of cardholder disputes with respect to amounts paid by the Discover Network. However, where the product or service is not scheduled to be provided to the customer until a later date following the purchase, the likelihood of a contingent payment obligation by the Discover Network increases. Losses related to merchant chargebacks were not material for the three months ended March 31, 2024 and 2023. The maximum potential amount of obligations of the Discover Network arising from such contingent obligations is estimated to be the portion of the total Discover Network transaction volume processed to date for which timely and valid disputes may be raised under applicable law and relevant issuer and customer agreements. There is no limitation on the maximum amount the Company may be liable to pay to issuers. However, the Company believes that such amount is not representative of the Company's actual potential loss exposure based on the Company's historical experience. The actual amount of the potential exposure cannot be quantified as the Company cannot determine whether the current or cumulative transaction volumes may include or result in disputed transactions. The following table summarizes certain information regarding merchant chargeback guarantees (dollars in millions): For the Three Months Ended March 31, 2024 2023 Aggregate sales transaction volume (1) $ 61,332 $ 60,833 (1) Represents transactions processed on the Discover Network for which a potential liability exists that, in aggregate, can differ from credit card sales volume. The Company did not record any contingent liability in the condensed consolidated financial statements for merchant chargeback guarantees as of March 31, 2024 and December 31, 2023. The Company mitigates the risk of potential loss exposure by withholding settlement from merchants, obtaining third-party guarantees, or obtaining escrow deposits or letters of credit from certain merchant acquirers or merchants that are considered a higher risk due to various factors such as time delays in the delivery of products or services. As of March 31, 2024 and December 31, 2023, the Company had escrow deposits and settlement withholdings of $9 million and $10 million, respectively, which are recorded in interest-bearing deposit accounts and accrued expenses and other liabilities on the Company's condensed consolidated statements of financial condition.

Litigation and Regulatory Matte

Litigation and Regulatory Matters	3 Months Ended
	Mar. 31, 2024
Loss Contingency [Abstract]
Litigation and Regulatory Matters	Litigation and Regulatory Matters In the normal course of business, from time to time, the Company has been named as a defendant in various legal actions, including arbitrations, class actions and other litigation, arising in connection with its activities. Certain of the actual or threatened legal actions include claims for substantial compensatory and/or punitive damages or claims for indeterminate amounts of damages. The litigation process is not predictable and can lead to unexpected results. The Company contests liability and/or the amount of damages as appropriate in each pending matter. The Company has historically offered its customers an arbitration clause in its customer agreements. The arbitration clause allows the Company and its customers to quickly and economically resolve disputes. Additionally, the arbitration clause has in some instances limited the costs of, and the Company's exposure to, litigation. Future legal and regulatory challenges and prohibitions may cause the Company to discontinue its offering and use of such clauses. From time to time, the Company is involved in legal actions challenging its arbitration clause. Bills may be periodically introduced in Congress to directly or indirectly prohibit the use of pre-dispute arbitration clauses. The Company is also involved, from time to time, in other reviews, investigations and proceedings (both formal and informal) by governmental agencies regarding the Company's business including, among other matters, regulatory, accounting, tax and other operational matters. The investigations and proceedings may result in significant adverse judgments, settlements, fines, penalties, injunctions, decreases in regulatory ratings, customer restitution or other relief. These outcomes could materially impact the Company's condensed consolidated financial statements, increase its cost of operations, or limit the Company's ability to execute its business strategies and engage in certain business activities. Certain subsidiaries of the Company are subject to consent orders with the Consumer Financial Protection Bureau ("CFPB") and FDIC, as described below. Pursuant to powers granted under federal banking laws, regulatory agencies have broad and sweeping discretion and may assess civil money penalties, require changes to certain business practices or require customer restitution at any time. In accordance with applicable accounting guidance, the Company establishes a liability for legal and regulatory matters when those matters create loss contingencies that are both probable and estimable. Except as discussed below regarding the card product misclassification matter, litigation and regulatory settlement-related expenses were immaterial for the three months ended March 31, 2024 and 2023. There may be an exposure to loss in excess of any amounts accrued. The Company believes the estimate of the aggregate range of reasonably possible losses (meaning the likelihood of losses is more than remote but less than likely), in excess of the amounts that the Company has accrued for legal and regulatory proceedings, is up to $230 million as of March 31, 2024. This estimated range of reasonably possible losses is based on currently available information for those proceedings in which the Company is involved and considers the Company's best estimate of such losses for those matters for which an estimate can be made. It does not represent the Company's maximum potential loss exposure. Various aspects of the legal proceedings underlying the estimated range will change from time to time and actual results may vary significantly from the estimate. The Company's estimated range noted above involves significant judgment, given the varying stages of the proceedings, the existence of numerous yet to be resolved issues, the breadth of the claims (often spanning multiple years and, in some cases, a wide range of business activities), unspecified damages and/or the novelty of the legal issues presented. The outcome of pending matters could adversely affect the Company's reputation and be material to the Company's condensed consolidated financial condition, operating results and cash flows for a particular future period, depending on, among other things, the level of the Company's income for such period. In July 2015, the Company announced that its subsidiaries, Discover Bank, The Student Loan Corporation and Discover Products Inc. (the "Discover Subsidiaries"), agreed to a consent order with the CFPB with respect to certain private student loan servicing practices (the "2015 Order"). The 2015 Order expired in July 2020. In December 2020, the Discover Subsidiaries agreed to a consent order (the "2020 Order") with the CFPB resolving the agency’s investigation into Discover Bank’s compliance with the 2015 Order. In connection with the 2020 Order, Discover is required to implement a redress and compliance plan and must pay at least $10 million in consumer redress to consumers who may have been harmed and has paid a $25 million civil money penalty to the CFPB. On September 25, 2023, following the consent of the Board of Directors of Discover Bank, the FDIC issued a consent order (the "2023 Order") to Discover Bank. The 2023 Order addresses shortcomings in Discover Bank’s compliance management system for consumer protection laws and related matters. It does not contain any monetary penalties or fines. As part of the 2023 Order, Discover Bank agreed to improve its consumer compliance management system and enhance related corporate governance and enterprise risk management practices, and increase the level of Board oversight of such matters. Discover Bank has been taking significant steps to strengthen the organization’s compliance management system and address the other issues identified in the 2023 Order. In addition, Discover added two new independent directors with significant banking experience to the Boards of Discover and Discover Bank in the third quarter of 2023. Management and the Board are committed to meeting all the requirements of the 2023 Order. Discover Bank is working diligently to complete items required by the 2023 Order. This includes having retained third party consultants to conduct independent reviews and the submission of action plans to the FDIC by the required deadlines for review and feedback. The actions completed to date, taken together with actions previously undertaken to improve and enhance its compliance management system and enhance related corporate governance, address multiple consent order objectives, however, many provisions require longer term implementation. Depending on regulatory feedback, the timing of approvals and sustainability periods, necessary work is not likely to be completed until at least 2025. On March 8, 2016, a class-action lawsuit was filed against the Company, other credit card networks, other issuing banks and EMVCo in the U.S. District Court for the Northern District of California (B&R Supermarket, Inc., d/b/a Milam's Market, et al. v. Visa, Inc., et al.) alleging a conspiracy by defendants to shift fraud liability to merchants with the migration to the EMV security standard and chip technology. The plaintiffs assert joint and several liability among the defendants and seek unspecified damages, including treble damages, attorneys' fees, costs and injunctive relief. The Company filed its motion to compel arbitration, motion for summary judgment, and Daubert challenges on November 30, 2022, and awaits rulings. The Company is not in a position at this time to assess the likely outcome or its exposure, if any, with respect to this matter. However, the Company will seek to defend itself vigorously against all claims asserted by the plaintiffs. Card Product Misclassification As reported, the Company recorded a liability of $365 million as of June 30, 2023, within accrued expenses and other liabilities, to provide refunds to merchants and merchant acquirers as a result of the card product misclassification. Management completed the reclassification of card products in November 2023. As of December 31, 2023, the balance of the liability was $375 million, reflecting an additional $11 million for the estimated effect of the prior price tiering on discount and interchange assessments recorded in each of the third and fourth quarters of 2023 and $12 million of settlement disbursements made through that date. Throughout the first quarter of 2024, the Company continued settlement discussions with large direct merchants both directly and indirectly as plaintiffs in putative class actions filed on behalf of all merchants, and the Company continued to discuss these efforts with its regulators. Another $9 million in settlement disbursements were made during the first quarter of 2024. Based on its experience to date with remediation efforts, discussions through the first quarter of 2024 with its regulators, Board of Directors and other stakeholders, the pending merger with Capital One approved by the Board of Directors during the quarter, and a desire to advance resolution of the matter more quickly to mitigate further risk, the Company determined it was appropriate to increase its estimate of total remediation. As a result, the Company increased its liability to $1.2 billion through a charge to other expense for the three months ended March 31, 2024, to reflect the total amount the Company now expects is probable to be disbursed in relation to the card product misclassification. The Company remains in discussions with its regulators regarding this matter. The Company expects these discussions will likely result in enforcement actions, which may include, among other remedies, monetary penalties, the amount of which cannot be estimated at this time and could be material. In addition, the Company and its subsidiaries have been named as defendants in various lawsuits, including a putative class action on behalf of shareholders and shareholder derivative actions. The Company also is cooperating with a Securities and Exchange Commission investigation into the card product misclassification matter. The Company believes that additional losses are probable as a result of these actions and such losses could be material but it is not able to make a reasonable estimate of the amount or range of such losses as of March 31, 2024.

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2024
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. Accounting Standards Codification ("ASC") Topic 820, Fair Value Measurement , provides a three-level hierarchy for classifying the inputs to valuation techniques used to measure fair value of financial instruments based on whether the inputs are observable or unobservable. It also requires certain disclosures about those measurements. The three-level valuation hierarchy is as follows: • Level 1 : Fair values determined by Level 1 inputs are defined as those that utilize quoted prices (unadjusted) in active markets for identical assets or liabilities that the Company has the ability to access. • Level 2 : Fair values determined by Level 2 inputs are those that utilize inputs other than quoted prices included in Level 1 that are observable for the asset or liability, either directly or indirectly. Level 2 inputs include quoted prices for similar assets and liabilities in active or inactive markets, quoted prices for the identical assets in an inactive market and inputs other than quoted prices that are observable for the asset or liability, such as interest rates and yield curves that are observable at commonly quoted intervals. The Company evaluates factors such as the frequency of transactions, the size of the bid-ask spread and the significance of adjustments made when considering transactions involving similar assets or liabilities to assess the relevance of those observed prices. If relevant and observable prices are available, the fair values of the related assets or liabilities would be classified as Level 2. • Level 3 : Fair values determined by Level 3 inputs are those based on unobservable inputs and include situations where there is little, if any, market activity for the asset or liability being valued. In instances where the inputs used to measure fair value may fall into different levels of the fair value hierarchy, the level in the fair value hierarchy in which the measurements are classified is based on the lowest level input that is significant to the fair value measurement in its entirety. Accordingly, the Company may utilize both observable and unobservable inputs in determining the fair values of financial instruments classified within the Level 3 category. The Company evaluates the classification of each fair value measurement within the hierarchy at least quarterly. The Company's assessment of the significance of a particular input to the fair value measurement in its entirety requires judgment and involves consideration of factors specific to the asset or liability. Furthermore, certain techniques used to measure fair value involve some degree of judgment and, as a result, are not necessarily indicative of the amounts the Company would realize in a current market exchange. Assets and Liabilities Measured at Fair Value on a Recurring Basis Assets and liabilities measured at fair value on a recurring basis are as follows (dollars in millions): Quoted Price Significant Significant Total Balance at March 31, 2024 Assets Fair value - OCI U.S. Treasury and U.S. GSE securities $ 12,815 $ 7 $ — $ 12,822 Residential mortgage-backed securities - Agency — 439 — 439 Available-for-sale investment securities $ 12,815 $ 446 $ — $ 13,261 Derivative financial instruments - cash flow hedges (1) $ — $ 1 $ — $ 1 Liabilities Fair value - OCI Derivative financial instruments - cash flow hedges (1) $ — $ 6 $ — $ 6 Fair value - Net income Derivative financial instruments - fair value hedges (1) $ — $ 5 $ — $ 5 Balance at December 31, 2023 Assets Fair value - OCI U.S. Treasury and U.S. GSE securities $ 12,928 $ 9 $ — $ 12,937 Residential mortgage-backed securities - Agency — 465 — 465 Available-for-sale investment securities $ 12,928 $ 474 $ — $ 13,402 Derivative financial instruments - cash flow hedges (1) $ — $ 2 $ — $ 2 Fair value - Net income Marketable equity securities $ 1 $ — $ — $ 1 Derivative financial instruments - fair value hedges (1) $ — $ 2 $ — $ 2 . (1) Derivative instrument carrying values in an asset or liability position are presented as part of other assets or accrued expenses and other liabilities, respectively, in the Company's condensed consolidated statements of financial condition. Available-for-Sale Investment Securities Investment securities classified as available-for-sale consist of U.S. Treasury and U.S. GSE securities and RMBS. The fair value estimates of investment securities classified as Level 1, consisting of U.S. Treasury securities, are determined based on quoted market prices for the same securities. The fair value estimates of U.S. GSE securities and RMBS are classified as Level 2 and are valued by maximizing the use of relevant observable inputs, including quoted prices for similar securities, benchmark yield curves and market-corroborated inputs. The Company validates the fair value estimates provided by pricing services primarily by comparing to valuations obtained through other pricing sources. The Company evaluates pricing variances among different pricing sources to ensure that the valuations utilized are reasonable. The Company also corroborates the reasonableness of the fair value estimates with analysis of trends of significant inputs, such as market interest rate curves. The Company further performs due diligence in understanding the procedures and techniques performed by the pricing services to derive fair value estimates. At March 31, 2024, amounts reported in RMBS reflect U.S. government agency and U.S. GSE obligations issued by Ginnie Mae, Fannie Mae and Freddie Mac with an aggregate par value of $457 million, a weighted-average coupon of 4.10% and a weighted-average remaining maturity of four years. Derivative Financial Instruments The Company's derivative financial instruments consist of interest rate swaps and foreign exchange forward contracts. These instruments are classified as Level 2 as their fair values are estimated using proprietary pricing models, containing certain assumptions based on readily observable market-based inputs, including interest rate curves, option volatility and foreign currency forward and spot rates. In determining fair values, the pricing models use widely accepted valuation techniques, including discounted cash flow analysis on the expected cash flows of each derivative. This analysis reflects the contractual terms of the derivatives, including the period to maturity and the observable market-based inputs. The fair values of the interest rate swaps are determined using the market standard methodology of netting the discounted future fixed cash receipts (or payments) and the discounted expected variable cash payments (or receipts). The variable cash payments are based on an expectation of future interest rates derived from the observable market interest rate curves. The Company considers collateral and master netting agreements that mitigate credit exposure to counterparties in determining the counterparty credit risk valuation adjustment. The fair values of the currency instruments are valued by comparing the contracted forward exchange rate pertaining to the specific contract maturities to the current market exchange rate. The Company validates the fair value estimates of interest rate swaps primarily through comparison to the fair value estimates computed by the counterparties to each of the derivative transactions. The Company evaluates pricing variances among different pricing sources to ensure that the valuations utilized are reasonable. The Company also corroborates the reasonableness of the fair value estimates with analysis of trends of significant inputs, such as market interest rate curves. The Company performs due diligence in understanding the impact of any changes to the valuation techniques performed by proprietary pricing models before implementation, working closely with the third-party valuation service and reviewing the service's control objectives at least annually. The Company corroborates the fair value of foreign exchange forward contracts through independent calculation of the fair value estimates. Assets and Liabilities Measured at Fair Value on a Non-Recurring Basis The Company also has assets that, under certain conditions, are subject to measurement at fair value on a non-recurring basis. These assets include those associated with acquired businesses, including goodwill. For these assets, measurement at fair value in periods subsequent to the initial recognition of the assets may be applicable whenever one is tested for impairment. No impairments were recognized related to these assets during the three months ended March 31, 2024 and 2023. Financial Instruments Measured at Other Than Fair Value The following tables disclose the estimated fair value of the Company's financial assets and financial liabilities that are not required to be carried at fair value (dollars in millions): Balance at March 31, 2024 Quoted Prices in Active Markets Significant Significant Total Carrying Assets Amortized cost Residential mortgage-backed securities - Agency $ — $ 238 $ — $ 238 $ 261 Held-to-maturity investment securities $ — $ 238 $ — $ 238 $ 261 Net loan receivables $ — $ — $ 124,936 $ 124,936 $ 117,297 Carrying value approximates fair value (1) Cash and cash equivalents $ 14,004 $ — $ — $ 14,004 $ 14,004 Restricted cash $ 439 $ — $ — $ 439 $ 439 Accrued interest receivables (2) $ — $ 1,490 $ — $ 1,490 $ 1,490 Liabilities Amortized cost Time deposits (3) $ — $ 45,276 $ — $ 45,276 $ 45,242 Long-term borrowings - owed to securitization investors $ — $ 10,767 $ 61 $ 10,828 $ 10,933 Other long-term borrowings — 9,544 — 9,544 9,542 Long-term borrowings $ — $ 20,311 $ 61 $ 20,372 $ 20,475 Carrying value approximates fair value (1) Accrued interest payables (2) $ — $ 445 $ — $ 445 $ 445 Balance at December 31, 2023 Assets Amortized cost Residential mortgage-backed securities - Agency $ — $ 234 $ — $ 234 $ 253 Held-to-maturity investment securities $ — $ 234 $ — $ 234 $ 253 Net loan receivables $ — $ — $ 126,940 $ 126,940 $ 119,126 Carrying value approximates fair value (1) Cash and cash equivalents $ 11,685 $ — $ — $ 11,685 $ 11,685 Restricted cash $ 43 $ — $ — $ 43 $ 43 Accrued interest receivables (2) $ — $ 1,450 $ — $ 1,450 $ 1,450 Liabilities Amortized cost Time deposits (3) $ — $ 45,333 $ — $ 45,333 $ 45,240 Short-term borrowings $ — $ 750 $ — $ 750 $ 750 Long-term borrowings - owed to securitization investors $ — $ 10,770 $ 65 $ 10,835 $ 10,993 Other long-term borrowings — 9,469 — 9,469 9,588 Long-term borrowings $ — $ 20,239 $ 65 $ 20,304 $ 20,581 Carrying value approximates fair value (1) Accrued interest payables (2) $ — $ 421 $ — $ 421 $ 421 (1) The carrying values of these assets and liabilities approximate fair value due to their short-term nature. (2) Accrued interest receivable and payable carrying values are presented as part of other assets and accrued expenses and other liabilities, respectively, in the Company's condensed consolidated statements of financial condition. (3) Excludes deposits without contractually defined maturities for all periods presented.

Derivatives and Hedging Activit

Derivatives and Hedging Activities	3 Months Ended
	Mar. 31, 2024
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivatives and Hedging Activities	Derivatives and Hedging Activities The Company uses derivatives to manage its exposure to various financial risks. The Company does not enter into derivatives for trading or speculative purposes. Certain derivatives used to manage the Company's exposure to foreign currency are not designated as hedges and do not qualify for hedge accounting. Derivatives may give rise to counterparty credit risk, which generally is mitigated through collateral arrangements as described under the sub-heading "— Collateral Requirements and Credit-Risk Related Contingency Features." The Company enters into derivative transactions with established dealers that meet minimum credit criteria established by the Company. All counterparties must be pre-approved before engaging in any transaction with the Company. The Company regularly monitors counterparties to ensure compliance with the Company's risk policies and limits. In determining the counterparty credit risk valuation adjustment for the fair values of derivatives, if any, the Company considers collateral and legally enforceable master netting agreements that mitigate credit exposure to related counterparties. All derivatives are recorded in other assets at their gross positive fair values and in accrued expenses and other liabilities at their gross negative fair values. See Note 14: Fair Value Measurements for a description of the valuation methodologies used for derivatives. Cash collateral amounts associated with derivative positions that are cleared through an exchange are legally characterized as settlement of the derivative positions. Such collateral amounts are reflected as offsets to the associated derivatives balances recorded in other assets or in accrued expenses and other liabilities. Other cash collateral posted and held balances are recorded in other assets and deposits, respectively, in the condensed consolidated statements of financial condition. Collateral amounts recorded in the condensed consolidated statements of financial condition are based on the net collateral posted or held position for each applicable legal entity's master netting arrangement with each counterparty. Derivatives Designated as Hedges Derivatives designated and qualifying as a hedge of the exposure to variability in expected future cash flows arising from changes in interest rates, or other types of forecasted transactions, are considered cash flow hedges. Derivatives designated and qualifying as a hedge of the exposure to changes in the fair value of an asset, liability, or firm commitment attributable to a particular risk, such as interest rate risk, are considered fair value hedges. Cash Flow Hedges The Company uses interest rate swaps to manage its exposure to variability in cash flows related to changes in interest rates on interest-earning assets and funding instruments. These interest rate swaps qualify for hedge accounting in accordance with ASC Topic 815, Derivatives and Hedging ("ASC 815"). At March 31, 2024 and December 31, 2023, the Company's outstanding cash flow hedges primarily relate to interest receipts from credit card receivables and had an initial maximum period of five years. The change in the fair value of derivatives designated as cash flow hedges is recorded in OCI and is subsequently reclassified into earnings in the period that the hedged forecasted cash flows affect earnings. Amounts reported in AOCI related to derivatives at March 31, 2024, will be reclassified to interest income and interest expense as interest receipts and payments are accrued on the Company's then outstanding credit card receivables and certain floating-rate debt, respectively. During the next 12 months, the Company estimates it will reclassify $104 million into pretax earnings related to its cash flow hedges. Fair Value Hedges The Company is exposed to changes in the fair value of its fixed-rate debt obligations due to changes in interest rates. The Company uses interest rate swaps to manage its exposure to changes in the fair value of certain fixed-rate long-term borrowings, including securitized debt and bank notes, and deposits attributable to changes in the respective benchmark rates. These interest rate swaps qualify as fair value hedges in accordance with ASC 815. Changes in the fair values of both (i) the derivatives and (ii) the hedged long-term borrowings and deposits attributable to the interest-rate risk being hedged are recorded in interest expense and generally provide substantial offset to one another. Derivatives Not Designated as Hedges Foreign Exchange Forward Contracts The Company has foreign exchange forward contracts that are economic hedges and are not designated as accounting hedges. The Company enters into foreign exchange forward contracts to manage foreign currency risk. Changes in the fair value of these contracts are recorded in other income on the condensed consolidated statements of income. Derivatives Cleared Through an Exchange Cash variation margin payments on derivatives cleared through an exchange are legally considered settlement payments and are accounted for with corresponding derivative positions as one unit of account and not presented separately as collateral. With settlement payments on derivative positions cleared through this exchange reflected as offsets to the associated derivative asset and liability balances, the fair values of derivative instruments and collateral balances shown are generally reduced. Derivatives Activity The following table summarizes the fair value (including accrued interest) and outstanding notional amounts of derivative instruments and related collateral balances (dollars in millions): March 31, 2024 December 31, 2023 Notional Number of Outstanding Derivative Contracts Derivative Assets Derivative Liabilities Notional Derivative Assets Derivative Liabilities Derivatives designated as hedges Interest rate swaps—cash flow hedge $ 12,000 19 $ 1 $ 6 $ 10,650 $ 2 $ — Interest rate swaps—fair value hedge $ 12,762 17 — 5 $ 8,650 2 — Derivatives not designated as hedges Foreign exchange forward contracts (1) $ 32 6 — — $ 29 — — Total gross derivative assets/liabilities (2) 1 11 4 — Less: collateral held/posted (3) — (11) — — Total net derivative assets/liabilities $ 1 $ — $ 4 $ — (1) The foreign exchange forward contracts have notional amounts of EUR 6 million, GBP 6 million, SGD 1 million and INR 1.5 billion as of March 31, 2024, and notional amounts of EUR 6 million, GBP 6 million, SGD 1 million, INR 1.1 billion and AUD 2 million as of December 31, 2023. (2) In addition to the derivatives disclosed in the table, the Company enters into forward contracts to purchase when-issued mortgage-backed securities and tax exempt single family mortgage revenue bonds as part of its community reinvestment initiatives. At March 31, 2024, the Company had one outstanding contract with a total notional amount of $23 million and an immaterial fair value. At December 31, 2023, the Company had one outstanding contract with a total notional amount of $35 million and an immaterial fair value. (3) Collateral amounts, which consist of cash and investment securities, are limited to the related derivative asset/liability balance and do not include excess collateral received/pledged. The following amounts were recorded on the statements of financial condition related to cumulative basis adjustments for fair value hedges (dollars in millions): March 31, 2024 December 31, 2023 Carrying Amount of Hedged Liabilities Cumulative Amount of Fair Value Hedging Adjustment (Decreasing) the Carrying Amount of Hedged Liabilities (1) Carrying Amount of Hedged Liabilities Cumulative Amount of Fair Value Hedging Adjustment (Decreasing) the Carrying Amount of Hedged Liabilities (1) Long-term borrowings $ 12,614 $ (108) $ 8,620 $ — (1) The balance includes $10 million and $12 million of cumulative hedging adjustments related to discontinued hedging relationships as of March 31, 2024 and December 31, 2023, respectively. The following table summarizes the impact of the derivative instruments on income and indicates where within the condensed consolidated financial statements such impact is reported (dollars in millions): Location and Amount of (Losses) Gains Recognized on the Condensed Consolidated Statements of Income Interest Expense Interest Income (Credit Card) Deposits Long-Term Borrowings For the Three Months Ended March 31, 2024 Total amounts of income and expense line items presented in the condensed consolidated statements of income, where the effects of fair value or cash flow hedges are recorded $ (1,210) $ (245) $ 3,938 The effects of cash flow and fair value hedging Gains (losses) on cash flow hedging relationships Amounts reclassified from OCI into earnings $ — $ 3 $ (40) Gains (losses) on fair value hedging relationships Gains on hedged items $ 3 $ 103 $ — Losses on interest rate swaps (4) (138) — Total losses on fair value hedging relationships $ (1) $ (35) $ — For the Three Months Ended March 31, 2023 Total amounts of income and expense line items presented in the condensed consolidated statements of income, where the effects of fair value or cash flow hedges are recorded $ (756) $ (189) $ 3,321 The effects of cash flow and fair value hedging Gains (losses) on cash flow hedging relationships Amounts reclassified from OCI into earnings $ — $ 2 $ (7) Gains (losses) on fair value hedging relationships Losses on hedged items $ — $ (35) $ — Gains on interest rate swaps — 21 — Total losses on fair value hedging relationships $ — $ (14) $ — For the impact of the derivative instruments on OCI, see Note 8: Accumulated Other Comprehensive Income. Collateral Requirements and Credit-Risk Related Contingency Features The Company has master netting arrangements and minimum collateral posting thresholds with its counterparties for its fair value and cash flow hedge interest rate swaps and foreign exchange forward contracts. The Company has not sought a legal opinion in relation to the enforceability of its master netting arrangements and, as such, does not report any of these positions on a net basis. Collateral is required by either the Company or its subsidiaries or the counterparty depending on the net fair value position of the derivatives held with that counterparty. These collateral receivable or payable amounts are generally not offset against the fair value of these derivatives but are recorded separately in other assets or deposits. Most of the Company's cash collateral amounts relate to positions cleared through an exchange and are reflected as offsets to the associated derivatives balances recorded in other assets and accrued expenses and other liabilities. The Company also has agreements with certain of its derivative counterparties that contain a provision under which the Company could be declared in default on any of its derivative obligations if the Company defaults on any of its indebtedness, including default where the lender has not accelerated repayment of the indebtedness.

Segment Disclosures

Segment Disclosures	3 Months Ended
	Mar. 31, 2024
Segment Reporting [Abstract]
Segment Disclosures	Segment Disclosures The Company manages its business activities in two segments: Digital Banking and Payment Services. • Digital Banking: The Digital Banking segment includes Discover-branded credit cards issued to individuals on the Discover Network and other consumer products and services, including private student loans, personal loans, home loans and deposit products. The majority of Digital Banking revenues relate to interest income earned on the segment's loan products. Additionally, the Company's credit card products generate substantially all revenues related to discount and interchange, protection products and loan fee income. • Payment Services: The Payment Services segment includes PULSE, an ATM, debit and electronic funds transfer network; Diners Club, a global payments network; and the Company's Network Partners business, which provides payment transaction processing and settlement services on the Discover Network. The majority of Payment Services revenues relate to transaction processing revenue from PULSE and royalty and licensee revenue from Diners Club. The business segment reporting provided to and used by the Company's CODM is prepared using the following principles and allocation conventions: • The Company aggregates operating segments when determining reportable segments. • Corporate overhead is not allocated between segments; all corporate overhead is included in the Digital Banking segment. • Through its operation of the Discover Network, the Digital Banking segment incurs fixed marketing, servicing and infrastructure costs that are not specifically allocated among the segments, except for an allocation of direct and incremental costs driven by the Company's Payment Services segment. • The Company's assets are not allocated among the operating segments in the information reviewed by the Company's CODM. • The revenues of each segment are derived from external sources. The segments do not earn revenue from intercompany sources. • Income taxes are not specifically allocated between the operating segments in the information reviewed by the Company's CODM. The following table presents segment data (dollars in millions): Digital Payment Total For the Three Months Ended March 31, 2024 Interest income Credit card loans $ 3,938 $ — $ 3,938 Private student loans 264 — 264 Personal loans 333 — 333 Other loans 115 — 115 Other interest income 298 — 298 Total interest income 4,948 — 4,948 Interest expense 1,461 — 1,461 Net interest income 3,487 — 3,487 Provision for credit losses 1,497 — 1,497 Other income 591 132 723 Other expense 2,259 50 2,309 Income before income taxes $ 322 $ 82 $ 404 For the Three Months Ended March 31, 2023 Interest income Credit card loans $ 3,321 $ — $ 3,321 Private student loans 252 — 252 Personal loans 248 — 248 Other loans 64 — 64 Other interest income 192 — 192 Total interest income 4,077 — 4,077 Interest expense 945 — 945 Net interest income 3,132 — 3,132 Provision for credit losses 1,102 — 1,102 Other income 522 88 610 Other expense 1,342 41 1,383 Income before income taxes $ 1,210 $ 47 $ 1,257

Revenue from Contracts with Cus

Revenue from Contracts with Customers	3 Months Ended
	Mar. 31, 2024
Revenue from Contract with Customer [Abstract]
Revenue from Contracts with Customers	Revenue from Contracts with Customers ASC Topic 606, Revenue from Contracts with Customers ("ASC 606"), generally applies to the sales of any good or service for which no other specific accounting guidance is provided. ASC 606 defines a principles-based model under which revenue from a contract is allocated to the distinct performance obligations within the contract and recognized in income as each performance obligation is satisfied. The Company's revenue that is subject to this model includes discount and interchange, protection products fees, transaction processing revenue and certain amounts classified as other income. The following table presents revenue from contracts with customers disaggregated by business segment and reconciles revenue from contracts with customers to total other income (dollars in millions): Digital Banking Payment Services Total For the Three Months Ended March 31, 2024 Other income subject to ASC 606 Discount and interchange revenue, net (1) $ 346 $ 25 $ 371 Protection products revenue 42 — 42 Transaction processing revenue — 87 87 Other income 3 20 23 Total other income subject to ASC 606 (2) 391 132 523 Other income not subject to ASC 606 Loan fee income 200 — 200 Total other income not subject to ASC 606 200 — 200 Total other income by operating segment $ 591 $ 132 $ 723 For the Three Months Ended March 31, 2023 Other income subject to ASC 606 Discount and interchange revenue, net (1) $ 310 $ 20 $ 330 Protection products revenue 43 — 43 Transaction processing revenue — 67 67 Other income 3 19 22 Total other income subject to ASC 606 (2) 356 106 462 Other income not subject to ASC 606 Loan fee income 166 — 166 Gains (losses) on equity investments — (18) (18) Total other income (loss) not subject to ASC 606 166 (18) 148 Total other income by operating segment $ 522 $ 88 $ 610 (1) Net of rewards, including Cashback Bonus rewards, of $703 million and $716 million for the three months ended March 31, 2024 and 2023, respectively. (2) Excludes $2 million and $6 million of deposit product fees that are reported within net interest income for the three months ended March 31, 2024 and 2023, respectively. For a detailed description of the Company's significant revenue recognition accounting policies, see Note 2: Summary of Significant Accounting Policies to the consolidated financial statements in the Company's annual report on Form 10-K for the year ended December 31, 2023.

Subsequent Events

Subsequent Events	3 Months Ended
	Mar. 31, 2024
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events The Company has evaluated events and transactions that have occurred subsequent to March 31, 2024, and determined that there were no subsequent events that would require recognition or disclosure in the condensed consolidated financial statements.

Background and Basis of Prese_2

Background and Basis of Presentation (Policies)	3 Months Ended
	Mar. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of presentation	The accompanying condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the U.S. ("GAAP") for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by GAAP for complete consolidated financial statements. In the opinion of management, the financial statements reflect all adjustments necessary for the fair presentation of results for the interim period. All such adjustments are of a normal, recurring nature.
Use of estimates	The preparation of financial statements in conformity with GAAP requires the Company to make estimates and assumptions that affect the amounts reported in the condensed consolidated financial statements and related disclosures. These estimates are based on information available as of the date of the condensed consolidated financial statements. The Company believes that the estimates used in the preparation of the condensed consolidated financial statements are reasonable. Actual results could differ from these estimates.

Investments (Tables)

Investments (Tables)	3 Months Ended
	Mar. 31, 2024
Investments, Debt and Equity Securities [Abstract]
Schedule of Investment Securities	The Company's investment securities consist of the following (dollars in millions): March 31, December 31, U.S. Treasury (1) and U.S. GSE (2) securities $ 12,822 $ 12,937 Residential mortgage-backed securities - Agency (3) 700 718 Total investment securities $ 13,522 $ 13,655 (1) Includes $377 million and $320 million of U.S. Treasury securities pledged as swap collateral as of March 31, 2024 and December 31, 2023, respectively. (2) Consists of securities issued by the Federal Home Loan Bank ("FHLB"). (3) Primarily consists of securities issued by Fannie Mae, Freddie Mac, or Ginnie Mae.
Schedule of Amortized Cost, Gross Unrealized Gains, Gross Unrealized Losses and Fair Value	The amortized cost, gross unrealized gains and losses and fair value of available-for-sale and held-to-maturity investment securities are as follows (dollars in millions): Amortized Gross Gross Fair Value At March 31, 2024 Available-for-Sale Investment Securities (1) U.S. Treasury and U.S. GSE securities $ 12,981 $ 10 $ (169) $ 12,822 Residential mortgage-backed securities - Agency 458 — (19) 439 Total available-for-sale investment securities $ 13,439 $ 10 $ (188) $ 13,261 Held-to-Maturity Investment Securities (2) Residential mortgage-backed securities - Agency (3) $ 261 $ — $ (23) $ 238 Total held-to-maturity investment securities $ 261 $ — $ (23) $ 238 At December 31, 2023 Available-for-Sale Investment Securities (1) U.S. Treasury and U.S. GSE securities $ 12,971 $ 52 $ (86) $ 12,937 Residential mortgage-backed securities - Agency 480 — (15) 465 Total available-for-sale investment securities $ 13,451 $ 52 $ (101) $ 13,402 Held-to-Maturity Investment Securities (2) Residential mortgage-backed securities - Agency (3) $ 253 $ — $ (19) $ 234 Total held-to-maturity investment securities $ 253 $ — $ (19) $ 234 (1) Available-for-sale investment securities are reported at fair value. (2) Held-to-maturity investment securities are reported at amortized cost. (3) Amounts represent residential mortgage-backed securities ("RMBS") that were classified as held-to-maturity as they were entered into as a part of the Company's community reinvestment initiatives.
Debt Securities, Available-for-Sale, Unrealized Loss Position, Fair Value	The following table provides information about available-for-sale investment securities with aggregate gross unrealized losses and the length of time that individual investment securities have been in a continuous unrealized loss position (dollars in millions): Number of Securities in a Loss Position Less than 12 months More than 12 months Fair Unrealized Fair Unrealized At March 31, 2024 Available-for-Sale Investment Securities U.S. Treasury and U.S. GSE securities 186 $ 7,701 $ (97) $ 3,532 $ (72) Residential mortgage-backed securities - Agency 31 $ — $ — $ 439 $ (19) At December 31, 2023 Available-for-Sale Investment Securities U.S. Treasury and U.S. GSE securities 105 $ 3,513 $ (13) $ 3,978 $ (73) Residential mortgage-backed securities - Agency 31 $ — $ — $ 465 $ (15)
Schedule of Maturities of Available-for-Sale Debt Securities and Held-to-Maturity Debt Securities	Maturities of available-for-sale debt securities and held-to-maturity debt securities are provided in the following table (dollars in millions): At March 31, 2024 One Year After One After Five After Ten Total Available-for-Sale Investment Securities — Amortized Cost U.S. Treasury and U.S. GSE securities $ 2,005 $ 10,552 $ 424 $ — $ 12,981 Residential mortgage-backed securities - Agency (1) — 65 24 369 458 Total available-for-sale investment securities $ 2,005 $ 10,617 $ 448 $ 369 $ 13,439 Held-to-Maturity Investment Securities — Amortized Cost Residential mortgage-backed securities - Agency (1) $ — $ — $ — $ 261 $ 261 Total held-to-maturity investment securities $ — $ — $ — $ 261 $ 261 Available-for-Sale Investment Securities — Fair Values U.S. Treasury and U.S. GSE securities $ 1,971 $ 10,428 $ 423 $ — $ 12,822 Residential mortgage-backed securities - Agency (1) — 63 23 353 439 Total available-for-sale investment securities $ 1,971 $ 10,491 $ 446 $ 353 $ 13,261 Held-to-Maturity Investment Securities — Fair Values Residential mortgage-backed securities - Agency (1) $ — $ — $ — $ 238 $ 238 Total held-to-maturity investment securities $ — $ — $ — $ 238 $ 238 (1) Maturities of RMBS are reflective of the contractual maturities of the investment.

Loan Receivables (Tables)

Loan Receivables (Tables)	3 Months Ended
	Mar. 31, 2024
Receivables [Abstract]
Schedule of Loan Receivables	The Company's classes of receivables within the two portfolio segments are depicted in the following table (dollars in millions): March 31, December 31, Credit card loans (1)(2) $ 99,475 $ 102,259 Other loans (3) Private student loans (4) 10,480 10,352 Personal loans 10,107 9,852 Other loans 6,493 5,946 Total other loans 27,080 26,150 Total loan receivables 126,555 128,409 Allowance for credit losses (9,258) (9,283) Net loan receivables $ 117,297 $ 119,126 (1) Amounts include carrying values of $13.9 billion and $14.8 billion underlying investors' interest in trust debt at March 31, 2024 and December 31, 2023, respectively, and $15.2 billion and $15.6 billion in seller's interest at March 31, 2024 and December 31, 2023, respectively. See Note 4: Credit Card and Private Student Loan Securitization Activities for additional information. (2) Unbilled accrued interest receivable on credit card loans, which is presented as part of other assets in the Company's condensed consolidated statements of financial condition, was $746 million and $753 million at March 31, 2024 and December 31, 2023, respectively. (3) Accrued interest receivable on private student, personal and other loans, which is presented as part of other assets in the Company's condensed consolidated statements of financial condition, was $555 million, $72 million and $23 million, respectively, at March 31, 2024 and $522 million, $69 million and $21 million, respectively, at December 31, 2023. (4) At March 31, 2024 and December 31, 2023, the private student loan portfolio continued to be classified as held for investment and there were $6.3 billion of private student loans in repayment.
Schedule of Credit Risk Profile by FICO Score and Origination Year	The following table provides the distribution of the amortized cost basis (excluding accrued interest receivable presented in other assets) by the most recent FICO scores available for the Company's customers for credit card, private student and personal loan receivables (dollars in millions): Credit Risk Profile by FICO Score March 31, 2024 December 31, 2023 660 and Above Less than 660 660 and Above Less than 660 $ % $ % $ % $ % Credit card loans $ 79,207 80 % $ 20,268 20 % $ 82,238 80 % $ 20,021 20 % Private student loans by origination year (1)(2) 2024 $ 129 98 % $ 3 2 % 2023 1,399 94 % 91 6 % $ 1,010 94 % $ 69 6 % 2022 1,445 94 % 88 6 % 1,495 95 % 85 5 % 2021 1,411 94 % 92 6 % 1,468 94 % 91 6 % 2020 1,127 94 % 76 6 % 1,180 94 % 75 6 % Prior 4,277 93 % 342 7 % 4,537 93 % 342 7 % Total private student loans $ 9,788 93 % $ 692 7 % $ 9,690 94 % $ 662 6 % Personal loans by origination year 2024 $ 1,425 100 % $ 5 — % 2023 4,614 97 % 146 3 % $ 5,149 98 % $ 100 2 % 2022 2,244 92 % 191 8 % 2,604 93 % 187 7 % 2021 869 91 % 85 9 % 1,049 92 % 91 8 % 2020 285 92 % 25 8 % 355 92 % 29 8 % Prior 185 85 % 33 15 % 247 86 % 41 14 % Total personal loans $ 9,622 95 % $ 485 5 % $ 9,404 95 % $ 448 5 % (1) FICO score represents the higher credit score of the cosigner or borrower.
Schedule of Delinquent Loans by Origination Year	The amortized cost basis (excluding accrued interest receivable presented in other assets) of delinquent loans in the Company's loan portfolio is shown below for credit card, private student and personal loan receivables (dollars in millions): March 31, 2024 December 31, 2023 30-89 Days 90 or Total Past 30-89 Days 90 or Total Past Credit card loans $ 1,869 $ 1,941 $ 3,810 $ 2,038 $ 1,917 $ 3,955 Private student loans by origination year (1) 2024 $ — $ — $ — 2023 2 1 3 $ — $ — $ — 2022 10 6 16 7 2 9 2021 18 10 28 18 6 24 2020 20 10 30 20 7 27 Prior 143 51 194 156 55 211 Total private student loans $ 193 $ 78 $ 271 $ 201 $ 70 $ 271 Personal loans by origination year 2024 $ — $ — $ — 2023 38 12 50 $ 26 $ 8 $ 34 2022 41 15 56 44 16 60 2021 17 6 23 20 8 28 2020 5 2 7 7 2 9 Prior 7 4 11 7 5 12 Total personal loans $ 108 $ 39 $ 147 $ 104 $ 39 $ 143 (1) Private student loans may include a deferment period, during which borrowers are not required to make payments while enrolled in school at least half time as determined by the school. During a deferment period, these loans do not advance into delinquency.
Schedule of Changes in the Allowance for Credit Losses	The following tables provide changes in the Company's allowance for credit losses (dollars in millions): For the Three Months Ended March 31, 2024 Credit Card Loans Private Student Loans Personal Loans Other Loans Total Loans Balance at December 31, 2023 $ 7,619 $ 858 $ 722 $ 84 $ 9,283 Additions Provision for credit losses (1) 1,333 53 134 11 1,531 Deductions Charge-offs (1,649) (47) (113) (3) (1,812) Recoveries 238 5 13 — 256 Net charge-offs (1,411) (42) (100) (3) (1,556) Balance at March 31, 2024 $ 7,541 $ 869 $ 756 $ 92 $ 9,258 For the Three Months Ended March 31, 2023 Credit Card Loans Private Student Loans Personal Loans Other Loans Total Loans Balance at December 31, 2022 $ 5,883 $ 839 $ 595 $ 57 $ 7,374 Cumulative effect of ASU No. 2022-02 adoption (2) (66) — (2) — (68) Balance at January 1, 2023 5,817 839 593 57 7,306 Additions Provision for credit losses (1) 1,002 60 68 5 1,135 Deductions Charge-offs (879) (33) (54) — (966) Recoveries 195 6 15 — 216 Net charge-offs (684) (27) (39) — (750) Balance at March 31, 2023 $ 6,135 $ 872 $ 622 $ 62 $ 7,691 (1) Excludes a $34 million and $33 million adjustment of the liability for expected credit losses on unfunded commitments for the three months ended March 31, 2024 and 2023, respectively, as the liability is recorded in accrued expenses and other liabilities in the Company's condensed consolidated statements of financial condition. (2) Represents the adjustment to the allowance for credit losses as a result of the adoption of ASU No. 2022-02 on January 1, 2023, which eliminated the requirement to apply discounted cash flow measurements for certain troubled debt restructurings.
Schedule of Net Charge-offs of Interest and Fee Revenues on Loan Receivables	Net charge-offs of principal are recorded against the allowance for credit losses, as shown in the preceding table. Information regarding net charge-offs of interest and fee revenues on credit card and other loans is as follows (dollars in millions): For the Three Months Ended March 31, 2024 2023 Interest and fees accrued subsequently charged-off, net of recoveries (recorded as a reduction of interest income) $ 279 $ 128 Fees accrued subsequently charged-off, net of recoveries (recorded as a reduction to other income) $ 69 $ 41
Schedule of Gross Charge Offs from Loan Receivables	Gross principal charge-offs of the Company's loan portfolio are presented in the table below, on a year-to-date basis, for credit card, private student and personal loan receivables (dollars in millions): For the Three Months Ended March 31, 2024 2023 Credit card loans $ 1,649 $ 879 Private student loans by origination year 2024 $ — 2023 — $ — 2022 2 — 2021 5 2 2020 6 5 Prior 34 26 Total private student loans $ 47 $ 33 Personal loans by origination year 2024 $ — 2023 28 $ — 2022 48 16 2021 22 18 2020 8 9 Prior 7 11 Total personal loans $ 113 $ 54
Schedule of Delinquent and Non-Accruing Loans	The amortized cost basis (excluding accrued interest receivable presented in other assets) of delinquent and non-accruing loans in the Company's loan portfolio is shown below for each class of loan receivables (dollars in millions): (1) 30-89 Days 90 or Total Past 90 or Total Non-accruing (2) At March 31, 2024 Credit card loans $ 1,869 $ 1,941 $ 3,810 $ 1,900 $ 203 Other loans Private student loans 193 78 271 77 8 Personal loans 108 39 147 37 11 Other loans 33 21 54 3 56 Total other loans 334 138 472 117 75 Total loan receivables $ 2,203 $ 2,079 $ 4,282 $ 2,017 $ 278 At December 31, 2023 Credit card loans $ 2,038 $ 1,917 $ 3,955 $ 1,881 $ 197 Other loans Private student loans 201 70 271 69 8 Personal loans 104 39 143 37 11 Other loans 39 19 58 3 53 Total other loans 344 128 472 109 72 Total loan receivables $ 2,382 $ 2,045 $ 4,427 $ 1,990 $ 269 (1) The payment status of both modified and unmodified loans is included in this table. (2) The Company estimates that the gross interest income that would have been recorded under the original terms of non-accruing credit card loans was $9 million and $8 million for the three months ended March 31, 2024 and 2023, respectively. The Company does not separately track the amount of gross interest income that would have been recorded under the original terms of loans. Instead, the Company estimated this amount based on customers' current balances and most recent interest rates.
Schedule of Financing Receivables in Modification , Amortized Cost Basis	The following table provides the period-end amortized cost basis, by modification category, of loans to borrowers experiencing financial difficulty that entered a modification program during the period (dollars in millions). Some of the loans presented in the table below may no longer be enrolled in a program at period-end: For the Three Months Ended March 31, 2024 2023 Credit card loans (1)(2) Interest rate reduction $ 920 $ 632 Total credit card loans (3) $ 920 $ 632 % of total class of financing receivables 0.92 % 0.70 % Private student loans (1) Payment delay (4) $ 1 $ 3 Interest rate reduction and payment delay (4) 101 29 Total private student loans (3) $ 102 $ 32 % of total class of financing receivables 0.97 % 0.04 % Personal loans (1) Payment delay (4) $ 4 $ 2 Term extension (5) 10 8 Interest rate reduction and payment delay (4) 26 14 Interest rate reduction and term extension (5) 14 6 Total personal loans (3) $ 54 $ 30 % of total class of financing receivables 0.53 % 0.36 % (1) Accrued interest receivable (including unbilled accrued interest receivable for credit card loans) on modified loans to borrowers experiencing financial difficulty, which is presented as part of other assets in the Company's condensed consolidated statements of financial condition, was immaterial at March 31, 2024 and 2023. (2) Accounts that entered a credit card loan modification program include $185 million and $118 million that were converted from revolving line-of-credit arrangements to term loans during the three months ended March 31, 2024 and 2023, respectively. (3) For settlements, the amortized cost basis is zero at period-end and therefore there is no amount reported for principal forgiveness in the table above. See financial effects table below for principal forgiveness to borrowers experiencing financial difficulty. (4) The Company defines a payment delay as a temporary reduction in payments below the original contractually required payment amounts (e.g., interest only payments). The Company's credit card loan modification programs do not result in an other than insignificant delay in payment.
Schedule of Loan Modification Effects	The following table provides information on the financial effects of loan modifications to borrowers experiencing financial difficulty, by modification type, made during the period (dollars in millions): For the Three Months Ended March 31, 2024 2023 Credit card loans Weighted-average interest rate reduction 14.42 % 13.38 % Principal forgiven $ 56 NM Interest and fees forgiven (1) $ 56 $ 12 Private student loans Weighted-average interest rate reduction 8.84 % 8.02 % Payment delay duration (in months) (2) 6 to 12 6 to 12 Personal loans Weighted-average interest rate reduction 13.20 % 11.55 % Weighted-average term extension (in months) 40 38 Payment delay duration (in months) (2) 6 to 12 6 to 12 (1) Represents the amount of interest and fees forgiven resulting from accounts entering into a credit card loan modification program and pre-charge off settlements. Interest and fees forgiven are reversed against the respective line items in the condensed consolidated statements of income. (2) For private student loan payment delays, the Company offers up to six consecutive months of delay and limits assistance to a life of loan maximum of 36 months. For personal loan payment delays, the Company limits this assistance to a life of loan maximum of 12 months.
Schedule of Financing Receivable, Past Due, Modified	The following table presents the payment status and period-end amortized cost basis, by class of loan receivable, of loans that were modified to borrowers experiencing financial difficulty during the 12 months preceding each of the periods presented (dollars in millions) (1) : Current 30-89 Days 90 or At March 31, 2024 Credit card loans $ 2,118 $ 257 $ 217 Private student loans 207 22 8 Personal loans 126 23 4 Total $ 2,451 $ 302 $ 229 At December 31, 2023 Credit card loans $ 1,882 $ 252 $ 196 Private student loans 147 18 8 Personal loans 109 20 4 Total $ 2,138 $ 290 $ 208 (1) This table includes any loan that entered a modification program during the preceding 12 months without regard to whether it remained in a modification program as of the reporting date.
Schedule of Financing Receivable, Modified, Subsequent Default	The following table presents the defaulted amount and period-end amortized cost basis, by modification category, of loans that defaulted during the period and were modified to borrowers experiencing financial difficulty during the 12 months preceding default (dollars in millions): For the Three Months Ended March 31, 2024 Defaulted Amount (1) Period-end Amortized Cost Basis Credit card loans Interest rate reduction $ 205 $ 161 Total credit card loans $ 205 $ 161 Private student loans Payment delay $ 2 $ 2 Interest rate reduction and payment delay 17 16 Total private student loans $ 19 $ 18 Personal loans Payment delay $ 1 $ 1 Term extension 2 1 Interest rate reduction and payment delay 7 3 Interest rate reduction and term extension 4 3 Total personal loans $ 14 $ 8 (1) For purposes of this disclosure, a loan is considered to be defaulted when it is 60 days or more delinquent at month end and has advanced two stages of delinquency subsequent to modification. Loans that entered a modification program in any stage of delinquency but did not experience a further payment default are included in the payment status table above but are not counted as defaulted for purposes of this disclosure. The defaulted amount and period-end amortized cost basis of loans modified on or after January 1, 2023 to borrowers experiencing financial difficulty which subsequently defaulted was immaterial for the three months ended March 31, 2023, for all classes of loan receivables.

Credit Card and Private Stude_2

Credit Card and Private Student Loan Securitization Activities (Tables)	3 Months Ended
	Mar. 31, 2024
Variable Interest Entities Disclosure [Abstract]
Schedule of Restricted Credit Card Securitized Assets	The carrying values of these restricted assets, which are presented on the Company's condensed consolidated statements of financial condition as relating to securitization activities, are shown in the following table (dollars in millions): March 31, December 31, Restricted cash $ 432 $ 36 Investors' interests held by third-party investors 10,975 11,725 Investors' interests held by wholly-owned subsidiaries of Discover Bank 2,917 3,117 Seller's interest 15,155 15,598 Loan receivables (1) 29,047 30,440 Allowance for credit losses allocated to securitized loan receivables (1) (1,323) (1,347) Net loan receivables 27,724 29,093 Other assets 3 2 Carrying value of assets of consolidated variable interest entities $ 28,159 $ 29,131 (1) The Company maintains its allowance for credit losses at an amount equal to lifetime expected credit losses associated with all loan receivables, which includes all loan receivables in the trusts. Therefore, the credit risk associated with the transferred receivables is fully reflected on the Company's statements of financial condition in accordance with GAAP.

Deposits (Tables)

Deposits (Tables)	3 Months Ended
	Mar. 31, 2024
Deposits [Abstract]
Schedule of Certificates of Deposit Maturities	The following table summarizes certificates of deposits maturing over the remainder of this year, over each of the next four years and thereafter (dollars in millions): At March 31, 2024 2024 $ 21,263 2025 12,190 2026 4,211 2027 4,408 2028 2,161 Thereafter 1,009 Total $ 45,242

Long-Term Borrowings (Tables)

Long-Term Borrowings (Tables)	3 Months Ended
	Mar. 31, 2024
Debt Disclosure [Abstract]
Schedule of Long-Term Borrowings and Weighted Average Interest Rates	Long-term borrowings consist of borrowings having original maturities of one year or more. The following table provides a summary of the Company's long-term borrowings and weighted-average interest rates on outstanding balances (dollars in millions): March 31, 2024 December 31, 2023 Maturity Interest Weighted-Average Interest Rate Outstanding Amount Outstanding Amount Securitized Debt Fixed-rate asset-backed securities (1) 2024-2026 0.58% - 5.03% 3.17% $ 9,947 $ 10,003 Floating-rate asset-backed securities (2) 2024 6.04% 6.04% 925 925 Total Discover Card Master Trust I and Discover Card Execution Note Trust 10,872 10,928 Floating-rate asset-backed security (3)(4) 2031 9.50% 9.50% 61 65 Total private student loan securitization trust 61 65 Total long-term borrowings - owed to securitization investors 10,933 10,993 Discover Financial Services (Parent Company) Fixed-rate senior notes 2024-2032 3.75% - 6.70% 4.68% 3,337 3,336 Fixed-rate retail notes 2025-2031 3.25% - 4.40% 3.82% 139 140 Fixed to floating-rate senior notes (5) 2034 7.96% 7.96% 992 993 Discover Bank Fixed-rate senior bank notes (1) 2024-2030 2.45% - 4.65% 3.53% 3,535 3,571 Fixed-rate subordinated bank notes 2028 5.97% 5.97% 491 500 Fixed-rate Federal Home Loan Bank advances 2030 4.77% - 4.82% 4.82% 523 523 Floating-rate Federal Home Loan Bank advances (6) 2024 5.49% - 5.59% 5.59% 525 525 Total long-term borrowings $ 20,475 $ 20,581 (1) The Company uses interest rate swaps to hedge portions of these long-term borrowings against changes in fair value attributable to changes in the applicable benchmark interest rates. The use of these interest rate swaps impacts the carrying value of the debt. See Note 15: Derivatives and Hedging Activities. (2) DCENT floating-rate asset-backed securities include issuances with the following interest rate terms: 1-month Term SOFR + 0.11448% Tenor Spread Adjustment + 60 basis points as of March 31, 2024. (3) The private student loan securitization trust floating-rate asset-backed security includes an issuance with the following interest rate term: Prime rate + 100 basis points as of March 31, 2024. (4) Repayment of this debt is dependent upon the timing of principal and interest payments on the underlying private student loans. The date shown represents the final maturity date. (5) The fixed to floating-rate senior notes include a rate reset on November 2, 2033, to a floating rate based on compounded SOFR + 3.370%. (6) The floating-rate FHLB advances include interest rate terms based on SOFR plus a spread ranging from 16 to 26 basis points as of March 31, 2024.
Schedule of Long-Term Borrowings Maturities	The following table summarizes long-term borrowings maturing over the remainder of this year, over each of the next four years and thereafter (dollars in millions): March 31, 2024 2024 $ 4,250 2025 6,121 2026 4,868 2027 1,001 2028 1,412 Thereafter 2,823 Total $ 20,475

Preferred Stock (Tables)

Preferred Stock (Tables)	3 Months Ended
	Mar. 31, 2024
Equity [Abstract]
Schedule of Stock by Class	The table below presents a summary of the Company's non-cumulative perpetual preferred stock that is outstanding at March 31, 2024 (dollars in millions, except per depositary share amounts): Series Description Initial Issuance Date Liquidation Preference and Redemption Price per Depositary Share (1) Per Annum Dividend Rate in effect at March 31, 2024 Total Depositary Shares Authorized, Issued and Outstanding Carrying Value March 31, 2024 December 31, 2023 March 31, 2024 December 31, 2023 C (2)(3)(4) Fixed-to-Floating Rate 10/31/2017 $ 1,000 5.500 % 570,000 570,000 $ 563 $ 563 D (2)(5)(6) Fixed-Rate Reset 6/22/2020 $ 1,000 6.125 % 500,000 500,000 493 493 Total Preferred Stock 1,070,000 1,070,000 $ 1,056 $ 1,056 (1) Redeemable at the redemption price plus declared and unpaid dividends. (2) Issued as depositary shares, each representing 1/100 th interest in a share of the corresponding series of preferred stock. Each preferred share has a par value of $0.01. (3) Redeemable at the Company’s option, subject to regulatory approval, either (i) in whole or in part on any dividend payment date on or after October 30, 2027, or (ii) in whole but not in part, at any time within 90 days following a regulatory capital treatment event (as defined in the certificate of designations for the Series C preferred stock). (4) Any dividends declared are payable semi-annually in arrears at a rate of 5.500% per annum until October 30, 2027. Thereafter, dividends declared will be payable quarterly in arrears at a floating rate equal to 3-month Term SOFR plus a spread of 3.338% per annum. (5) Redeemable at the Company’s option, subject to regulatory approval, either (i) in whole or in part during the three-month period prior to, and including, each reset date (as defined in the certificate of designations for the Series D preferred stock) or (ii) in whole but not in part, at any time within 90 days following a regulatory capital treatment event (as defined in the certificate of designations for the Series D Preferred Stock). (6) Any dividends declared are payable semi-annually in arrears at a rate of 6.125% per annum until September 23, 2025, after which the dividend rate will reset every 5 years to a fixed annual rate equal to the 5-year Treasury plus a spread of 5.783%.

Accumulated Other Comprehensi_2

Accumulated Other Comprehensive Income (Tables)	3 Months Ended
	Mar. 31, 2024
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Schedule of Changes in Accumulated Other Comprehensive Income (Loss)	Changes in each component of accumulated other comprehensive (loss) income ("AOCI") were as follows (dollars in millions): Unrealized (Losses) Gains on Available-for-Sale Investment Securities, Net of Tax (Losses) Gains on Cash Flow Hedges, Net of Tax Losses on Pension Plan, Net of Tax AOCI For the Three Months Ended March 31, 2024 Balance at December 31, 2023 $ (37) $ (8) $ (180) $ (225) Net change (97) (71) — (168) Balance at March 31, 2024 $ (134) $ (79) $ (180) $ (393) For the Three Months Ended March 31, 2023 Balance at December 31, 2022 $ (136) $ (14) $ (189) $ (339) Net change 92 12 — 104 Balance at March 31, 2023 $ (44) $ (2) $ (189) $ (235)
Schedule of Other Comprehensive Income Before Reclassifications and Amounts Reclassified from AOCI	The following table presents each component of other comprehensive income ("OCI") before reclassifications and amounts reclassified from AOCI for each component of OCI before- and after-tax (dollars in millions): Before Tax Tax Benefit (Expense) Net of Tax For the Three Months Ended March 31, 2024 Available-for-Sale Investment Securities Net unrealized holding losses arising during the period $ (129) $ 32 $ (97) Net change $ (129) $ 32 $ (97) Cash Flow Hedges Net unrealized losses arising during the period $ (131) $ 32 $ (99) Amounts reclassified from AOCI 37 (9) 28 Net change $ (94) $ 23 $ (71) For the Three Months Ended March 31, 2023 Available-for-Sale Investment Securities Net unrealized holding gains arising during the period $ 122 $ (30) $ 92 Net change $ 122 $ (30) $ 92 Cash Flow Hedges Net unrealized gains arising during the period $ 10 $ (2) $ 8 Amounts reclassified from AOCI 5 (1) 4 Net change $ 15 $ (3) $ 12

Income Taxes (Tables)

Income Taxes (Tables)	3 Months Ended
	Mar. 31, 2024
Income Tax Disclosure [Abstract]
Schedule of Effective Income Tax Rate Calculation	The following table presents the calculation of the Company's effective income tax rate (dollars in millions): For the Three Months Ended March 31, 2024 2023 Income before income taxes $ 404 $ 1,257 Income tax expense $ 96 $ 289 Effective income tax rate 23.7 % 23.0 %

Earnings Per Share (Tables)

Earnings Per Share (Tables)	3 Months Ended
	Mar. 31, 2024
Earnings Per Share [Abstract]
Schedule of Basic and Diluted EPS	The following table presents the calculation of basic and diluted earnings per share ("EPS") (dollars and shares in millions, except per share amounts): For the Three Months Ended March 31, 2024 2023 Numerator Net income $ 308 $ 968 Preferred stock dividends (31) (31) Net income available to common stockholders 277 937 Income allocated to participating securities (3) (6) Net income allocated to common stockholders $ 274 $ 931 Denominator Weighted-average shares of common stock outstanding 250 262 Weighted-average shares of common stock outstanding and common stock equivalents 250 262 Basic earnings per common share $ 1.10 $ 3.55 Diluted earnings per common share $ 1.10 $ 3.55

Capital Adequacy (Tables)

Capital Adequacy (Tables)	3 Months Ended
	Mar. 31, 2024
Broker-Dealer, Net Capital Requirement, SEC Regulation [Abstract]
Schedule of Minimum and Well-Capitalized Requirements	The following table shows the actual capital amounts and ratios of DFS and Discover Bank and comparisons of each to the regulatory minimum and "well-capitalized" requirements (dollars in millions): Actual Minimum Capital Capital Requirements Amount Ratio (1) Amount Ratio Amount (2) Ratio (2) March 31, 2024 Total capital (to risk-weighted assets) Discover Financial Services $ 17,513 13.3 % $ 10,499 ≥8.0% $ 13,124 ≥10.0% Discover Bank $ 16,598 12.8 % $ 10,349 ≥8.0% $ 12,936 ≥10.0% Tier 1 capital (to risk-weighted assets) Discover Financial Services $ 15,394 11.7 % $ 7,874 ≥6.0% $ 7,874 ≥6.0% Discover Bank $ 13,752 10.6 % $ 7,762 ≥6.0% $ 10,349 ≥8.0% Tier 1 capital (to average assets) Discover Financial Services $ 15,394 10.1 % $ 6,086 ≥4.0% N/A N/A Discover Bank $ 13,752 9.2 % $ 6,004 ≥4.0% $ 7,505 ≥5.0% Common Equity Tier 1 (to risk-weighted assets) Discover Financial Services $ 14,338 10.9 % $ 5,906 ≥4.5% N/A N/A Discover Bank $ 13,752 10.6 % $ 5,821 ≥4.5% $ 8,409 ≥6.5% December 31, 2023 Total capital (to risk-weighted assets) Discover Financial Services $ 17,986 13.7 % $ 10,471 ≥8.0% $ 13,088 ≥10.0% Discover Bank $ 16,856 13.0 % $ 10,352 ≥8.0% $ 12,939 ≥10.0% Tier 1 capital (to risk-weighted assets) Discover Financial Services $ 15,872 12.1 % $ 7,853 ≥6.0% $ 7,853 ≥6.0% Discover Bank $ 13,910 10.8 % $ 7,764 ≥6.0% $ 10,352 ≥8.0% Tier 1 capital (to average assets) Discover Financial Services $ 15,872 10.7 % $ 5,915 ≥4.0% N/A N/A Discover Bank $ 13,910 9.5 % $ 5,833 ≥4.0% $ 7,292 ≥5.0% Common Equity Tier 1 (to risk-weighted assets) Discover Financial Services $ 14,816 11.3 % $ 5,890 ≥4.5% N/A N/A Discover Bank $ 13,910 10.8 % $ 5,823 ≥4.5% $ 8,411 ≥6.5% (1) Capital ratios are calculated based on the Basel III standardized approach rules, subject to applicable transition provisions, including CECL transition provisions. (2) The Basel III rules do not establish well-capitalized thresholds for these measures for bank holding companies. Existing well-capitalized thresholds established in the Federal Reserve's Regulation Y have been included where available.

Commitments, Contingencies an_2

Commitments, Contingencies and Guarantees (Tables)	3 Months Ended
	Mar. 31, 2024
Guarantor Obligations [Line Items]
Schedule of Maximum Potential Counterparty Exposures Related to Settlement Guarantees and Merchant Chargeback Guarantee	The following table summarizes certain information regarding merchant chargeback guarantees (dollars in millions): For the Three Months Ended March 31, 2024 2023 Aggregate sales transaction volume (1) $ 61,332 $ 60,833 (1) Represents transactions processed on the Discover Network for which a potential liability exists that, in aggregate, can differ from credit card sales volume.

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2024
Fair Value Disclosures [Abstract]
Schedule of Assets and Liabilities Measured at Fair Value on a Recurring Basis	Assets and liabilities measured at fair value on a recurring basis are as follows (dollars in millions): Quoted Price Significant Significant Total Balance at March 31, 2024 Assets Fair value - OCI U.S. Treasury and U.S. GSE securities $ 12,815 $ 7 $ — $ 12,822 Residential mortgage-backed securities - Agency — 439 — 439 Available-for-sale investment securities $ 12,815 $ 446 $ — $ 13,261 Derivative financial instruments - cash flow hedges (1) $ — $ 1 $ — $ 1 Liabilities Fair value - OCI Derivative financial instruments - cash flow hedges (1) $ — $ 6 $ — $ 6 Fair value - Net income Derivative financial instruments - fair value hedges (1) $ — $ 5 $ — $ 5 Balance at December 31, 2023 Assets Fair value - OCI U.S. Treasury and U.S. GSE securities $ 12,928 $ 9 $ — $ 12,937 Residential mortgage-backed securities - Agency — 465 — 465 Available-for-sale investment securities $ 12,928 $ 474 $ — $ 13,402 Derivative financial instruments - cash flow hedges (1) $ — $ 2 $ — $ 2 Fair value - Net income Marketable equity securities $ 1 $ — $ — $ 1 Derivative financial instruments - fair value hedges (1) $ — $ 2 $ — $ 2 . (1) Derivative instrument carrying values in an asset or liability position are presented as part of other assets or accrued expenses and other liabilities, respectively, in the Company's condensed consolidated statements of financial condition.
Schedule of Financial Instruments Measured at Other Than Fair Value	The following tables disclose the estimated fair value of the Company's financial assets and financial liabilities that are not required to be carried at fair value (dollars in millions): Balance at March 31, 2024 Quoted Prices in Active Markets Significant Significant Total Carrying Assets Amortized cost Residential mortgage-backed securities - Agency $ — $ 238 $ — $ 238 $ 261 Held-to-maturity investment securities $ — $ 238 $ — $ 238 $ 261 Net loan receivables $ — $ — $ 124,936 $ 124,936 $ 117,297 Carrying value approximates fair value (1) Cash and cash equivalents $ 14,004 $ — $ — $ 14,004 $ 14,004 Restricted cash $ 439 $ — $ — $ 439 $ 439 Accrued interest receivables (2) $ — $ 1,490 $ — $ 1,490 $ 1,490 Liabilities Amortized cost Time deposits (3) $ — $ 45,276 $ — $ 45,276 $ 45,242 Long-term borrowings - owed to securitization investors $ — $ 10,767 $ 61 $ 10,828 $ 10,933 Other long-term borrowings — 9,544 — 9,544 9,542 Long-term borrowings $ — $ 20,311 $ 61 $ 20,372 $ 20,475 Carrying value approximates fair value (1) Accrued interest payables (2) $ — $ 445 $ — $ 445 $ 445 Balance at December 31, 2023 Assets Amortized cost Residential mortgage-backed securities - Agency $ — $ 234 $ — $ 234 $ 253 Held-to-maturity investment securities $ — $ 234 $ — $ 234 $ 253 Net loan receivables $ — $ — $ 126,940 $ 126,940 $ 119,126 Carrying value approximates fair value (1) Cash and cash equivalents $ 11,685 $ — $ — $ 11,685 $ 11,685 Restricted cash $ 43 $ — $ — $ 43 $ 43 Accrued interest receivables (2) $ — $ 1,450 $ — $ 1,450 $ 1,450 Liabilities Amortized cost Time deposits (3) $ — $ 45,333 $ — $ 45,333 $ 45,240 Short-term borrowings $ — $ 750 $ — $ 750 $ 750 Long-term borrowings - owed to securitization investors $ — $ 10,770 $ 65 $ 10,835 $ 10,993 Other long-term borrowings — 9,469 — 9,469 9,588 Long-term borrowings $ — $ 20,239 $ 65 $ 20,304 $ 20,581 Carrying value approximates fair value (1) Accrued interest payables (2) $ — $ 421 $ — $ 421 $ 421 (1) The carrying values of these assets and liabilities approximate fair value due to their short-term nature. (2) Accrued interest receivable and payable carrying values are presented as part of other assets and accrued expenses and other liabilities, respectively, in the Company's condensed consolidated statements of financial condition. (3) Excludes deposits without contractually defined maturities for all periods presented.

Derivatives and Hedging Activ_2

Derivatives and Hedging Activities (Tables)	3 Months Ended
	Mar. 31, 2024
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Fair Value and Outstanding Notional Amounts of Derivative Instruments and Related Collateral Balances	The following table summarizes the fair value (including accrued interest) and outstanding notional amounts of derivative instruments and related collateral balances (dollars in millions): March 31, 2024 December 31, 2023 Notional Number of Outstanding Derivative Contracts Derivative Assets Derivative Liabilities Notional Derivative Assets Derivative Liabilities Derivatives designated as hedges Interest rate swaps—cash flow hedge $ 12,000 19 $ 1 $ 6 $ 10,650 $ 2 $ — Interest rate swaps—fair value hedge $ 12,762 17 — 5 $ 8,650 2 — Derivatives not designated as hedges Foreign exchange forward contracts (1) $ 32 6 — — $ 29 — — Total gross derivative assets/liabilities (2) 1 11 4 — Less: collateral held/posted (3) — (11) — — Total net derivative assets/liabilities $ 1 $ — $ 4 $ — (1) The foreign exchange forward contracts have notional amounts of EUR 6 million, GBP 6 million, SGD 1 million and INR 1.5 billion as of March 31, 2024, and notional amounts of EUR 6 million, GBP 6 million, SGD 1 million, INR 1.1 billion and AUD 2 million as of December 31, 2023. (2) In addition to the derivatives disclosed in the table, the Company enters into forward contracts to purchase when-issued mortgage-backed securities and tax exempt single family mortgage revenue bonds as part of its community reinvestment initiatives. At March 31, 2024, the Company had one outstanding contract with a total notional amount of $23 million and an immaterial fair value. At December 31, 2023, the Company had one outstanding contract with a total notional amount of $35 million and an immaterial fair value. (3) Collateral amounts, which consist of cash and investment securities, are limited to the related derivative asset/liability balance and do not include excess collateral received/pledged.
Schedule of Hedged Items in Fair Value Hedging Relationship	The following amounts were recorded on the statements of financial condition related to cumulative basis adjustments for fair value hedges (dollars in millions): March 31, 2024 December 31, 2023 Carrying Amount of Hedged Liabilities Cumulative Amount of Fair Value Hedging Adjustment (Decreasing) the Carrying Amount of Hedged Liabilities (1) Carrying Amount of Hedged Liabilities Cumulative Amount of Fair Value Hedging Adjustment (Decreasing) the Carrying Amount of Hedged Liabilities (1) Long-term borrowings $ 12,614 $ (108) $ 8,620 $ — (1) The balance includes $10 million and $12 million of cumulative hedging adjustments related to discontinued hedging relationships as of March 31, 2024 and December 31, 2023, respectively.
Schedule of Impact of the Derivative Instruments on Income	The following table summarizes the impact of the derivative instruments on income and indicates where within the condensed consolidated financial statements such impact is reported (dollars in millions): Location and Amount of (Losses) Gains Recognized on the Condensed Consolidated Statements of Income Interest Expense Interest Income (Credit Card) Deposits Long-Term Borrowings For the Three Months Ended March 31, 2024 Total amounts of income and expense line items presented in the condensed consolidated statements of income, where the effects of fair value or cash flow hedges are recorded $ (1,210) $ (245) $ 3,938 The effects of cash flow and fair value hedging Gains (losses) on cash flow hedging relationships Amounts reclassified from OCI into earnings $ — $ 3 $ (40) Gains (losses) on fair value hedging relationships Gains on hedged items $ 3 $ 103 $ — Losses on interest rate swaps (4) (138) — Total losses on fair value hedging relationships $ (1) $ (35) $ — For the Three Months Ended March 31, 2023 Total amounts of income and expense line items presented in the condensed consolidated statements of income, where the effects of fair value or cash flow hedges are recorded $ (756) $ (189) $ 3,321 The effects of cash flow and fair value hedging Gains (losses) on cash flow hedging relationships Amounts reclassified from OCI into earnings $ — $ 2 $ (7) Gains (losses) on fair value hedging relationships Losses on hedged items $ — $ (35) $ — Gains on interest rate swaps — 21 — Total losses on fair value hedging relationships $ — $ (14) $ —

Segment Disclosures (Tables)

Segment Disclosures (Tables)	3 Months Ended
	Mar. 31, 2024
Segment Reporting [Abstract]
Schedule of Segment Disclosures	The following table presents segment data (dollars in millions): Digital Payment Total For the Three Months Ended March 31, 2024 Interest income Credit card loans $ 3,938 $ — $ 3,938 Private student loans 264 — 264 Personal loans 333 — 333 Other loans 115 — 115 Other interest income 298 — 298 Total interest income 4,948 — 4,948 Interest expense 1,461 — 1,461 Net interest income 3,487 — 3,487 Provision for credit losses 1,497 — 1,497 Other income 591 132 723 Other expense 2,259 50 2,309 Income before income taxes $ 322 $ 82 $ 404 For the Three Months Ended March 31, 2023 Interest income Credit card loans $ 3,321 $ — $ 3,321 Private student loans 252 — 252 Personal loans 248 — 248 Other loans 64 — 64 Other interest income 192 — 192 Total interest income 4,077 — 4,077 Interest expense 945 — 945 Net interest income 3,132 — 3,132 Provision for credit losses 1,102 — 1,102 Other income 522 88 610 Other expense 1,342 41 1,383 Income before income taxes $ 1,210 $ 47 $ 1,257

Revenue from Contracts with C_2

Revenue from Contracts with Customers (Tables)	3 Months Ended
	Mar. 31, 2024
Revenue from Contract with Customer [Abstract]
Schedule of Revenue from Contracts with Customers Disaggregated by Business Segment	The following table presents revenue from contracts with customers disaggregated by business segment and reconciles revenue from contracts with customers to total other income (dollars in millions): Digital Banking Payment Services Total For the Three Months Ended March 31, 2024 Other income subject to ASC 606 Discount and interchange revenue, net (1) $ 346 $ 25 $ 371 Protection products revenue 42 — 42 Transaction processing revenue — 87 87 Other income 3 20 23 Total other income subject to ASC 606 (2) 391 132 523 Other income not subject to ASC 606 Loan fee income 200 — 200 Total other income not subject to ASC 606 200 — 200 Total other income by operating segment $ 591 $ 132 $ 723 For the Three Months Ended March 31, 2023 Other income subject to ASC 606 Discount and interchange revenue, net (1) $ 310 $ 20 $ 330 Protection products revenue 43 — 43 Transaction processing revenue — 67 67 Other income 3 19 22 Total other income subject to ASC 606 (2) 356 106 462 Other income not subject to ASC 606 Loan fee income 166 — 166 Gains (losses) on equity investments — (18) (18) Total other income (loss) not subject to ASC 606 166 (18) 148 Total other income by operating segment $ 522 $ 88 $ 610 (1) Net of rewards, including Cashback Bonus rewards, of $703 million and $716 million for the three months ended March 31, 2024 and 2023, respectively. (2) Excludes $2 million and $6 million of deposit product fees that are reported within net interest income for the three months ended March 31, 2024 and 2023, respectively.

Background and Basis of Prese_3

Background and Basis of Presentation (Narrative) (Details) $ in Millions	3 Months Ended
	Mar. 31, 2024 USD ($) segment numberOfDirectors	Dec. 31, 2023 USD ($)
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of reportable segments (in number of segments) | segment	2
Recently Adopted Accounting Pronouncement [Line Items]
Retained Earnings (Accumulated Deficit)	$ (30,511)	$ (30,448)
Investment securities	(13,522)	(13,655)
Cumulative Effect, Period of Adoption, Adjustment | Accounting Standards update 2023-02
Recently Adopted Accounting Pronouncement [Line Items]
Retained Earnings (Accumulated Deficit)		37
Investment securities		23
Deferred Tax Assets, Net		$ 14
Discover Financial Services | Capital One Financial Corporation
Plan of Merger [Line Items]
Business Combination, Price of Acquisition, Expected	$ 35,300
Business Acquisition, Number of Common Stock Shares Issued for each Share of Acquiree Stock	1.0192
Business Acquisition Acquirer's Percentage Ownership in Combined Entity	0.60
Business Acquisition Acquiree's Percentage Ownership in Combined Entity	0.40
Business Acquisition, Number of Directors on Combined Entity BOD | numberOfDirectors	15
Business Acquisition, Number of Directors on Combined Entity BOD from Acquirer | numberOfDirectors	12
Business Acquisition, Number of Directors on Combined Entity BOD from Acquiree | numberOfDirectors	3

Investments (Narrative) (Detail

Investments (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Summary of Investment Holdings [Line Items]
Proceeds from the sale of available-for-sale securities	$ 0	$ 0
Debt Securities, Available-for-Sale, Gain (Loss)	0	$ 0
Contingent liabilities related to equity method investments	0		$ 0
Low Income Housing Tax Credit investments | Other Expense
Summary of Investment Holdings [Line Items]
Amortization Method Qualified Affordable Housing Project Investments, Amortization	16
Affordable Housing Tax Credits and Other Tax Benefits, Amount	18
Other Assets [Member] | Payment Services [Member]
Summary of Investment Holdings [Line Items]
Equity securities without readily determinable fair value	35		35
Other Assets [Member] | Community Reinvestment Act [Member]
Summary of Investment Holdings [Line Items]
Equity method investments	479		514
Other Liabilities [Member] | Community Reinvestment Act [Member]
Summary of Investment Holdings [Line Items]
Contingent liabilities related to equity method investments	$ 183		$ 187

Investments (Schedule of Invest

Investments (Schedule of Investment Securities) (Details) - USD ($) $ in Millions		Mar. 31, 2024	Dec. 31, 2023
Summary of Investment Holdings [Line Items]
Investment securities		$ 13,522	$ 13,655
US Treasury and Government
Summary of Investment Holdings [Line Items]
Investment securities	[1],[2]	12,822	12,937
Residential Mortgage-Backed Securities - Agency [Member]
Summary of Investment Holdings [Line Items]
Investment securities	[2]	700	718
U.S. Treasury Securities [Member] | Asset Pledged as Collateral [Member]
Summary of Investment Holdings [Line Items]
Derivative collateral		$ 377	$ 320
[1] Includes $377 million and $320 million of U.S. Treasury securities pledged as swap collateral as of March 31, 2024 and December 31, 2023, respectively. (2) Consists of securities issued by the Federal Home Loan Bank ("FHLB").

Investments (Schedule of Amorti

Investments (Schedule of Amortized Cost, Gross Unrealized Gains, Gross Unrealized Losses and Fair Value) (Details) - USD ($) $ in Millions		Mar. 31, 2024		Dec. 31, 2023
Summary of Investment Holdings [Line Items]
Available-for-sale investment securities, amortized cost	[1]	$ 13,439		$ 13,451
Available-for-sale investment securities, gross unrealized gains	[1]	10		52
Available-for-sale investment securities, gross unrealized losses	[1]	(188)		(101)
Available-for-sale investment securities, fair value	[1]	13,261		13,402
Held-to-maturity investment securities, amortized cost	[2]	261		253
Held-to-maturity investment securities, gross unrealized gains	[2]	0		0
Held-to-maturity investment securities, gross unrealized losses	[2]	(23)		(19)
Held-to-maturity investment securities, fair value	[2]	238		234
US Treasury and Government
Summary of Investment Holdings [Line Items]
Available-for-sale investment securities, amortized cost	[1]	12,981		12,971
Available-for-sale investment securities, gross unrealized gains	[1]	10		52
Available-for-sale investment securities, gross unrealized losses	[1]	(169)		(86)
Available-for-sale investment securities, fair value	[1]	12,822		12,937
Residential Mortgage-Backed Securities - Agency [Member]
Summary of Investment Holdings [Line Items]
Available-for-sale investment securities, amortized cost	[1]	458	[3]	480
Available-for-sale investment securities, gross unrealized gains	[1]	0		0
Available-for-sale investment securities, gross unrealized losses	[1]	(19)		(15)
Available-for-sale investment securities, fair value	[1]	439	[3]	465
Held-to-maturity investment securities, amortized cost	[2],[4]	261	[3]	253
Held-to-maturity investment securities, gross unrealized gains	[2],[4]	0		0
Held-to-maturity investment securities, gross unrealized losses	[2],[4]	(23)		(19)
Held-to-maturity investment securities, fair value	[2],[4]	$ 238	[3]	$ 234
[1] Available-for-sale investment securities are reported at fair value. Held-to-maturity investment securities are reported at amortized cost. Maturities of RMBS are reflective of the contractual maturities of the investment. Amounts represent residential mortgage-backed securities ("RMBS") that were classified as held-to-maturity as they were entered into as a part of the Company's community reinvestment initiatives.

Investments (Schedule of Fair V

Investments (Schedule of Fair Value of Securities in a Continuous Unrealized Loss Position for Less Than 12 Months and More Than 12 Months) (Details) $ in Millions	Mar. 31, 2024 USD ($) securities	Dec. 31, 2023 USD ($) securities
US Treasury and Government
Summary of Investment Holdings [Line Items]
Available-for-sale investment securities, continuous unrealized loss position, number of securities | securities	186	105
Available-for-sale investment securities, continuous unrealized loss position, less than 12 months, fair value	$ 7,701	$ 3,513
Available-for-sale securities, continuous unrealized loss position, less than 12 months, accumulated loss	(97)	(13)
Debt securities, available-for-sale, continuous unrealized loss position, 12 months or longer, fair value	3,532	3,978
Available-for-sale investment securities, continuous unrealized loss position, more than 12 months, unrealized losses	$ (72)	$ (73)
Residential Mortgage-Backed Securities - Agency [Member]
Summary of Investment Holdings [Line Items]
Available-for-sale investment securities, continuous unrealized loss position, number of securities | securities	31	31
Available-for-sale investment securities, continuous unrealized loss position, less than 12 months, fair value	$ 0	$ 0
Available-for-sale securities, continuous unrealized loss position, less than 12 months, accumulated loss	0	0
Debt securities, available-for-sale, continuous unrealized loss position, 12 months or longer, fair value	439	465
Available-for-sale investment securities, continuous unrealized loss position, more than 12 months, unrealized losses	$ (19)	$ (15)

Investments (Schedule of Maturi

Investments (Schedule of Maturities of Available-for-Sale Debt Securities and Held-to-Maturity Debt Securities) (Details) - USD ($) $ in Millions		Mar. 31, 2024		Dec. 31, 2023
Summary of Investment Holdings [Line Items]
Available-for-sale investment securities, debt maturities, one year or less, amortized cost		$ 2,005
Available-for-sale investment securities, debt maturities, after one year through five years, amortized cost		10,617
Available-for-sale investment securities, debt maturities, after five years through ten years, amortized cost		448
Available-for-sale investment securities, debt maturities, after ten years, amortized cost		369
Available-for-sale investment securities, amortized cost	[1]	13,439		$ 13,451
Held-to-maturity investment securities, debt maturities, one year or less, amortized cost		0
Held-to-maturity investment securities, debt maturities, after one year through five years, amortized cost		0
Held-to-maturity investment securities, debt maturities, after five years through ten years, amortized cost		0
Held-to-maturity investment securities, debt maturities, after ten years, amortized cost		261
Held-to-maturity investment securities, amortized cost	[2]	261		253
Available-for-sale investment securities, debt maturities, one year or less, fair value		1,971
Available-for-sale investment securities, debt maturities, after one year through five years, fair value		10,491
Available-for-sale investment securities, debt maturities, after five years through ten years, fair value		446
Available-for-sale investment securities, debt maturities, after ten years, fair value		353
Available-for-sale investment securities, fair value	[1]	13,261		13,402
Held-to-maturity investment securities, debt maturities, one year or less, fair value		0
Held-to-maturity investment securities, debt maturities, after one year through five years, fair value		0
Held-to-maturity investment securities, debt maturities, after five years through ten years, fair value		0
Held-to-maturity investment securities, debt maturities, after ten years, fair value		238
Held-to-maturity investment securities, fair value	[2]	238		234
US Treasury and Government
Summary of Investment Holdings [Line Items]
Available-for-sale investment securities, debt maturities, one year or less, amortized cost		2,005
Available-for-sale investment securities, debt maturities, after one year through five years, amortized cost		10,552
Available-for-sale investment securities, debt maturities, after five years through ten years, amortized cost		424
Available-for-sale investment securities, debt maturities, after ten years, amortized cost		0
Available-for-sale investment securities, amortized cost	[1]	12,981		12,971
Available-for-sale investment securities, debt maturities, one year or less, fair value		1,971
Available-for-sale investment securities, debt maturities, after one year through five years, fair value		10,428
Available-for-sale investment securities, debt maturities, after five years through ten years, fair value		423
Available-for-sale investment securities, debt maturities, after ten years, fair value		0
Available-for-sale investment securities, fair value	[1]	12,822		12,937
Residential Mortgage-Backed Securities - Agency [Member]
Summary of Investment Holdings [Line Items]
Available-for-sale investment securities, debt maturities, one year or less, amortized cost	[3]	0
Available-for-sale investment securities, debt maturities, after one year through five years, amortized cost	[3]	65
Available-for-sale investment securities, debt maturities, after five years through ten years, amortized cost	[3]	24
Available-for-sale investment securities, debt maturities, after ten years, amortized cost	[3]	369
Available-for-sale investment securities, amortized cost	[1]	458	[3]	480
Held-to-maturity investment securities, debt maturities, one year or less, amortized cost	[3]	0
Held-to-maturity investment securities, debt maturities, after one year through five years, amortized cost	[3]	0
Held-to-maturity investment securities, debt maturities, after five years through ten years, amortized cost	[3]	0
Held-to-maturity investment securities, debt maturities, after ten years, amortized cost	[3]	261
Held-to-maturity investment securities, amortized cost	[2],[4]	261	[3]	253
Available-for-sale investment securities, debt maturities, one year or less, fair value	[3]	0
Available-for-sale investment securities, debt maturities, after one year through five years, fair value	[3]	63
Available-for-sale investment securities, debt maturities, after five years through ten years, fair value	[3]	23
Available-for-sale investment securities, debt maturities, after ten years, fair value	[3]	353
Available-for-sale investment securities, fair value	[1]	439	[3]	465
Held-to-maturity investment securities, debt maturities, one year or less, fair value	[3]	0
Held-to-maturity investment securities, debt maturities, after one year through five years, fair value	[3]	0
Held-to-maturity investment securities, debt maturities, after five years through ten years, fair value	[3]	0
Held-to-maturity investment securities, debt maturities, after ten years, fair value	[3]	238
Held-to-maturity investment securities, fair value	[2],[4]	$ 238	[3]	$ 234
[1] Available-for-sale investment securities are reported at fair value. Held-to-maturity investment securities are reported at amortized cost. Maturities of RMBS are reflective of the contractual maturities of the investment. Amounts represent residential mortgage-backed securities ("RMBS") that were classified as held-to-maturity as they were entered into as a part of the Company's community reinvestment initiatives.

Loan Receivables (Narrative) (D

Loan Receivables (Narrative) (Details) $ in Millions	3 Months Ended
	Mar. 31, 2024 USD ($) segment	Dec. 31, 2023 USD ($)	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loan portfolio segments (in segments) | segment	2
Allowance for credit losses	$ 9,258	$ 9,283			$ 7,691	$ 7,374
Allowance for credit losses, period increase (decrease)	$ (25)
Expected EOY Unemployment Rate	4.03%
Expected Future Peak Unemployment Rate	4.17%
Expected EY Annualized Increase in GDP	2.48%
Reasonable and supportable forecast period	18 months	18 months	18 months	18 months	18 months
Reversion period	12 months				12 months
Minimum [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Delinquent Loan Qualification Period	30 days
Personal Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Temporary Reduced Payment Program, Maximum Period of Payment Reduction	12 months
Maximum repayment term for permanent modification programs (in years)	9 years
Credit Card Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses	$ 7,541	$ 7,619			$ 6,135	5,883
Temporary Reduced Payment Program, Maximum Period of Payment Reduction	12 months
Permanent workout program maturity (in months)	72 months
Interest and fees forgiven due to loan modification program	$ 56				12
Total Other Loans [Member] | Private Student Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses	869	858			872	839
Total Other Loans [Member] | Personal Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses	$ 756	$ 722			$ 622	$ 595

Loan Receivables (Schedule of L

Loan Receivables (Schedule of Loan Receivables) (Details) - USD ($) $ in Millions		Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan receivables		$ 126,555	$ 128,409
Allowance for credit losses		(9,258)	(9,283)	$ (7,691)	$ (7,374)
Net loan receivables		117,297	119,126
Variable Interest Entity, Primary Beneficiary [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan receivables		29,192	30,590
Allowance for credit losses		(1,323)	(1,347)
Credit Card Securitization Trusts [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan receivables	[1]	29,047	30,440
Allowance for credit losses	[1]	(1,323)	(1,347)
Net loan receivables		27,724	29,093
Seller's interest		15,155	15,598
Credit Card Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan receivables	[2],[3]	99,475	102,259
Allowance for credit losses		(7,541)	(7,619)	(6,135)	(5,883)
Accrued interest receivable		746	753
Credit Card Loans [Member] | Credit Card Securitization Trusts [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Investors' interest		13,900	14,800
Seller's interest		15,200	15,600
Total Other Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan receivables	[4]	27,080	26,150
Total Other Loans [Member] | Private Student Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan receivables	[4],[5]	10,480	10,352
Allowance for credit losses		(869)	(858)	(872)	(839)
Accrued interest receivable		555	522
Private student loans in repayment		6,300	6,300
Total Other Loans [Member] | Personal Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan receivables	[4]	10,107	9,852
Allowance for credit losses		(756)	(722)	(622)	(595)
Accrued interest receivable		72	69
Total Other Loans [Member] | Other Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan receivables	[4]	6,493	5,946
Allowance for credit losses		(92)	(84)	$ (62)	$ (57)
Accrued interest receivable		$ 23	$ 21
[1] The Company maintains its allowance for credit losses at an amount equal to lifetime expected credit losses associated with all loan receivables, which includes all loan receivables in the trusts. Therefore, the credit risk associated with the transferred receivables is fully reflected on the Company's statements of financial condition in accordance with GAAP. Amounts include carrying values of $13.9 billion and $14.8 billion underlying investors' interest in trust debt at March 31, 2024 and December 31, 2023, respectively, and $15.2 billion and $15.6 billion in seller's interest at March 31, 2024 and December 31, 2023, respectively. See Note 4: Credit Card and Private Student Loan Securitization Activities for additional information. Unbilled accrued interest receivable on credit card loans, which is presented as part of other assets in the Company's condensed consolidated statements of financial condition, was $746 million and $753 million at March 31, 2024 and December 31, 2023, respectively. Accrued interest receivable on private student, personal and other loans, which is presented as part of other assets in the Company's condensed consolidated statements of financial condition, was $555 million, $72 million and $23 million, respectively, at March 31, 2024 and $522 million, $69 million and $21 million, respectively, at December 31, 2023.

Loan Receivables (Schedule of C

Loan Receivables (Schedule of Credit Risk Profile by FICO Score and Origination Year) (Details) - USD ($) $ in Millions		Mar. 31, 2024	Dec. 31, 2023
Financing Receivable, Credit Quality Indicator [Line Items]
Loan receivables		$ 126,555	$ 128,409
Credit Card Loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loan receivables	[1],[2]	99,475	102,259
Credit Card Loans [Member] | FICO Score, 660 and Above [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loan receivables, credit card		$ 79,207	$ 82,238
FICO distribution %, credit card		80%	80%
Credit Card Loans [Member] | FICO Score, Less Than 660 Or No Score [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loan receivables, credit card		$ 20,268	$ 20,021
FICO distribution %, credit card		20%	20%
Total Other Loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loan receivables	[3]	$ 27,080	$ 26,150
Total Other Loans [Member] | Private Student Loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loan receivables	[3],[4]	10,480	10,352
Total Other Loans [Member] | Private Student Loans [Member] | FICO Score, 660 and Above [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loan receivables, originated in 2023	[5]	$ 129
FICO distribution %, originated in 2023	[5]	98%
Loan receivables, originated in 2022	[5]	$ 1,399	$ 1,010
FICO distribution %, originated in 2022	[5]	94%	94%
Loan receivables, originated in 2021	[5]	$ 1,445	$ 1,495
FICO distribution %, originated in 2021	[5]	94%	95%
Loan receivables, originated in 2020	[5]	$ 1,411	$ 1,468
FICO distribution %, originated in 2020	[5]	94%	94%
Loan receivables, originated in 2019	[5]	$ 1,127	$ 1,180
FICO distribution %, originated in 2019	[5]	94%	94%
Loan receivables, originated prior to 2019	[5]	$ 4,277	$ 4,537
FICO distribution %, originated prior to 2019	[5]	93%	93%
Loan receivables	[5]	$ 9,788	$ 9,690
FICO distribution %, loan receivables	[5]	93%	94%
Total Other Loans [Member] | Private Student Loans [Member] | FICO Score, Less Than 660 Or No Score [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loan receivables, originated in 2023	[5]	$ 3
FICO distribution %, originated in 2023	[5]	2%
Loan receivables, originated in 2022	[5]	$ 91	$ 69
FICO distribution %, originated in 2022	[5]	6%	6%
Loan receivables, originated in 2021	[5]	$ 88	$ 85
FICO distribution %, originated in 2021	[5]	6%	5%
Loan receivables, originated in 2020	[5]	$ 92	$ 91
FICO distribution %, originated in 2020	[5]	6%	6%
Loan receivables, originated in 2019	[5]	$ 76	$ 75
FICO distribution %, originated in 2019	[5]	6%	6%
Loan receivables, originated prior to 2019	[5]	$ 342	$ 342
FICO distribution %, originated prior to 2019	[5]	7%	7%
Loan receivables	[5]	$ 692	$ 662
FICO distribution %, loan receivables	[5]	7%	6%
Total Other Loans [Member] | Personal Loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loan receivables	[3]	$ 10,107	$ 9,852
Total Other Loans [Member] | Personal Loans [Member] | FICO Score, 660 and Above [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loan receivables, originated in 2023		$ 1,425
FICO distribution %, originated in 2023		100%
Loan receivables, originated in 2022		$ 4,614	$ 5,149
FICO distribution %, originated in 2022		97%	98%
Loan receivables, originated in 2021		$ 2,244	$ 2,604
FICO distribution %, originated in 2021		92%	93%
Loan receivables, originated in 2020		$ 869	$ 1,049
FICO distribution %, originated in 2020		91%	92%
Loan receivables, originated in 2019		$ 285	$ 355
FICO distribution %, originated in 2019		92%	92%
Loan receivables, originated prior to 2019		$ 185	$ 247
FICO distribution %, originated prior to 2019		85%	86%
Loan receivables		$ 9,622	$ 9,404
FICO distribution %, loan receivables		95%	95%
Total Other Loans [Member] | Personal Loans [Member] | FICO Score, Less Than 660 Or No Score [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loan receivables, originated in 2023		$ 5
FICO distribution %, originated in 2023		0%
Loan receivables, originated in 2022		$ 146	$ 100
FICO distribution %, originated in 2022		3%	2%
Loan receivables, originated in 2021		$ 191	$ 187
FICO distribution %, originated in 2021		8%	7%
Loan receivables, originated in 2020		$ 85	$ 91
FICO distribution %, originated in 2020		9%	8%
Loan receivables, originated in 2019		$ 25	$ 29
FICO distribution %, originated in 2019		8%	8%
Loan receivables, originated prior to 2019		$ 33	$ 41
FICO distribution %, originated prior to 2019		15%	14%
Loan receivables		$ 485	$ 448
FICO distribution %, loan receivables		5%	5%
[1] Amounts include carrying values of $13.9 billion and $14.8 billion underlying investors' interest in trust debt at March 31, 2024 and December 31, 2023, respectively, and $15.2 billion and $15.6 billion in seller's interest at March 31, 2024 and December 31, 2023, respectively. See Note 4: Credit Card and Private Student Loan Securitization Activities for additional information. Unbilled accrued interest receivable on credit card loans, which is presented as part of other assets in the Company's condensed consolidated statements of financial condition, was $746 million and $753 million at March 31, 2024 and December 31, 2023, respectively. Accrued interest receivable on private student, personal and other loans, which is presented as part of other assets in the Company's condensed consolidated statements of financial condition, was $555 million, $72 million and $23 million, respectively, at March 31, 2024 and $522 million, $69 million and $21 million, respectively, at December 31, 2023.

Loan Receivables (Schedule of D

Loan Receivables (Schedule of Delinquent Loans by Origination Year) (Details) - USD ($) $ in Millions		Mar. 31, 2024	Dec. 31, 2023
Financing Receivable, Credit Quality Indicator [Line Items]
Loan receivables		$ 126,555	$ 128,409
Credit Card Loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loan receivables	[1],[2]	99,475	102,259
Total Other Loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loan receivables	[3]	27,080	26,150
Total Other Loans [Member] | Private Student Loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loan receivables	[3],[4]	10,480	10,352
Total Other Loans [Member] | Personal Loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loan receivables	[3]	10,107	9,852
30-89 Days Delinquent [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loan receivables		2,203	2,382
30-89 Days Delinquent [Member] | Credit Card Loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loan receivables, credit card		1,869	2,038
30-89 Days Delinquent [Member] | Total Other Loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loan receivables		334	344
30-89 Days Delinquent [Member] | Total Other Loans [Member] | Private Student Loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loan receivables, originated in 2023	[5]	0
Loan receivables, originated in 2022	[5]	2	0
Loan receivables, originated in 2021	[5]	10	7
Loan receivables, originated in 2020	[5]	18	18
Loan receivables, originated in 2019	[5]	20	20
Loan receivables, originated prior to 2019	[5]	143	156
Loan receivables	[5]	193	201
30-89 Days Delinquent [Member] | Total Other Loans [Member] | Personal Loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loan receivables, originated in 2023		0
Loan receivables, originated in 2022		38	26
Loan receivables, originated in 2021		41	44
Loan receivables, originated in 2020		17	20
Loan receivables, originated in 2019		5	7
Loan receivables, originated prior to 2019		7	7
Loan receivables		108	104
90 or More Days Delinquent [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loan receivables		2,079	2,045
90 or More Days Delinquent [Member] | Credit Card Loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loan receivables, credit card		1,941	1,917
90 or More Days Delinquent [Member] | Total Other Loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loan receivables		138	128
90 or More Days Delinquent [Member] | Total Other Loans [Member] | Private Student Loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loan receivables, originated in 2023	[5]	0
Loan receivables, originated in 2022	[5]	1	0
Loan receivables, originated in 2021	[5]	6	2
Loan receivables, originated in 2020	[5]	10	6
Loan receivables, originated in 2019	[5]	10	7
Loan receivables, originated prior to 2019	[5]	51	55
Loan receivables	[5]	78	70
90 or More Days Delinquent [Member] | Total Other Loans [Member] | Personal Loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loan receivables, originated in 2023		0
Loan receivables, originated in 2022		12	8
Loan receivables, originated in 2021		15	16
Loan receivables, originated in 2020		6	8
Loan receivables, originated in 2019		2	2
Loan receivables, originated prior to 2019		4	5
Loan receivables		39	39
Total Past Due [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loan receivables		4,282	4,427
Total Past Due [Member] | Credit Card Loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loan receivables, credit card		3,810	3,955
Total Past Due [Member] | Total Other Loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loan receivables		472	472
Total Past Due [Member] | Total Other Loans [Member] | Private Student Loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loan receivables, originated in 2023	[5]	0
Loan receivables, originated in 2022	[5]	3	0
Loan receivables, originated in 2021	[5]	16	9
Loan receivables, originated in 2020	[5]	28	24
Loan receivables, originated in 2019	[5]	30	27
Loan receivables, originated prior to 2019	[5]	194	211
Loan receivables	[5]	271	271
Total Past Due [Member] | Total Other Loans [Member] | Personal Loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loan receivables, originated in 2023		0
Loan receivables, originated in 2022		50	34
Loan receivables, originated in 2021		56	60
Loan receivables, originated in 2020		23	28
Loan receivables, originated in 2019		7	9
Loan receivables, originated prior to 2019		11	12
Loan receivables		$ 147	$ 143
[1] Amounts include carrying values of $13.9 billion and $14.8 billion underlying investors' interest in trust debt at March 31, 2024 and December 31, 2023, respectively, and $15.2 billion and $15.6 billion in seller's interest at March 31, 2024 and December 31, 2023, respectively. See Note 4: Credit Card and Private Student Loan Securitization Activities for additional information. Unbilled accrued interest receivable on credit card loans, which is presented as part of other assets in the Company's condensed consolidated statements of financial condition, was $746 million and $753 million at March 31, 2024 and December 31, 2023, respectively. Accrued interest receivable on private student, personal and other loans, which is presented as part of other assets in the Company's condensed consolidated statements of financial condition, was $555 million, $72 million and $23 million, respectively, at March 31, 2024 and $522 million, $69 million and $21 million, respectively, at December 31, 2023. Private student loans may include a deferment period, during which borrowers are not required to make payments while enrolled in school at least half time as determined by the school. During a deferment period, these loans do not advance into delinquency.

Loan Receivables (Schedule of_2

Loan Receivables (Schedule of Changes in the Allowance for Credit Losses) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for credit losses, balance at beginning of period	$ 9,283	$ 7,374
Provision for credit losses(1)	1,531	1,135
Charge-offs	(1,812)	(966)
Recoveries	256	216
Net charge-offs	(1,556)	(750)
Allowance for credit losses, balance at end of period	9,258	7,691
Off-Balance-Sheet, Credit Loss, Liability, Credit Loss Expense (Reversal)	34	33
Cumulative Effect, Period of Adoption, Adjustment | Accounting Standards Update 2022-02
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for credit losses, balance at beginning of period		(68)
Cumulative Effect, Period of Adoption, Adjusted Balance | Accounting Standards Update 2022-02
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for credit losses, balance at beginning of period		7,306
Credit Card Loans [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for credit losses, balance at beginning of period	7,619	5,883
Provision for credit losses(1)	1,333	1,002
Charge-offs	(1,649)	(879)
Recoveries	238	195
Net charge-offs	(1,411)	(684)
Allowance for credit losses, balance at end of period	7,541	6,135
Credit Card Loans [Member] | Cumulative Effect, Period of Adoption, Adjustment | Accounting Standards Update 2022-02
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for credit losses, balance at beginning of period		(66)
Credit Card Loans [Member] | Cumulative Effect, Period of Adoption, Adjusted Balance | Accounting Standards Update 2022-02
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for credit losses, balance at beginning of period		5,817
Total Other Loans [Member] | Private Student Loans [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for credit losses, balance at beginning of period	858	839
Provision for credit losses(1)	53	60
Charge-offs	(47)	(33)
Recoveries	5	6
Net charge-offs	(42)	(27)
Allowance for credit losses, balance at end of period	869	872
Total Other Loans [Member] | Private Student Loans [Member] | Cumulative Effect, Period of Adoption, Adjustment | Accounting Standards Update 2022-02
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for credit losses, balance at beginning of period		0
Total Other Loans [Member] | Private Student Loans [Member] | Cumulative Effect, Period of Adoption, Adjusted Balance | Accounting Standards Update 2022-02
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for credit losses, balance at beginning of period		839
Total Other Loans [Member] | Personal Loans [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for credit losses, balance at beginning of period	722	595
Provision for credit losses(1)	134	68
Charge-offs	(113)	(54)
Recoveries	13	15
Net charge-offs	(100)	(39)
Allowance for credit losses, balance at end of period	756	622
Total Other Loans [Member] | Personal Loans [Member] | Cumulative Effect, Period of Adoption, Adjustment | Accounting Standards Update 2022-02
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for credit losses, balance at beginning of period		(2)
Total Other Loans [Member] | Personal Loans [Member] | Cumulative Effect, Period of Adoption, Adjusted Balance | Accounting Standards Update 2022-02
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for credit losses, balance at beginning of period		593
Total Other Loans [Member] | Other Loans [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for credit losses, balance at beginning of period	84	57
Provision for credit losses(1)	11	5
Charge-offs	(3)	0
Recoveries	0	0
Net charge-offs	(3)	0
Allowance for credit losses, balance at end of period	$ 92	62
Total Other Loans [Member] | Other Loans [Member] | Cumulative Effect, Period of Adoption, Adjustment | Accounting Standards Update 2022-02
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for credit losses, balance at beginning of period		0
Total Other Loans [Member] | Other Loans [Member] | Cumulative Effect, Period of Adoption, Adjusted Balance | Accounting Standards Update 2022-02
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for credit losses, balance at beginning of period		$ 57

Loan Receivables (Schedule of N

Loan Receivables (Schedule of Net Charge-offs of Interest and Fee Revenues on Loan Receivables) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Receivables [Abstract]
Interest and fees accrued subsequently charged-off, net of recoveries (recorded as a reduction of interest income)	$ 279	$ 128
Fees accrued subsequently charged-off, net of recoveries (recorded as a reduction to other income)	$ 69	$ 41

Loan Receivables (Schedule of G

Loan Receivables (Schedule of Gross Principal Charge-offs (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Financing Receivable, Loan Modifications [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff	$ 1,812	$ 966
Credit Card Loans [Member]
Financing Receivable, Loan Modifications [Line Items]
Financing Receivable Revolving Writeoff	1,649	879
Financing Receivable, Allowance for Credit Loss, Writeoff	1,649	879
Total Other Loans [Member] | Private Student Loans [Member]
Financing Receivable, Loan Modifications [Line Items]
Gross Principal Charge-off, Year One, Originated, Current Fiscal Year	0
Gross Principal Charge-off, Year Two, Originated, Year Before Current Fiscal Year	0	0
Gross Principal Charge-off, Year Three, Originated, Two Years Before Current Fiscal Year	2	0
Gross Principal Charge-off, Year Four, Originated, Three Years Before Current Fiscal Year	5	2
Gross Principal Charge-off, Year Five, Originated, Four Years Before Current Fiscal Year	6	5
Gross Principal Charge-off Originated More Than Five Years Before Current Fiscal Year	34	26
Financing Receivable, Allowance for Credit Loss, Writeoff	47	33
Total Other Loans [Member] | Personal Loans [Member]
Financing Receivable, Loan Modifications [Line Items]
Gross Principal Charge-off, Year One, Originated, Current Fiscal Year	0
Gross Principal Charge-off, Year Two, Originated, Year Before Current Fiscal Year	28	0
Gross Principal Charge-off, Year Three, Originated, Two Years Before Current Fiscal Year	48	16
Gross Principal Charge-off, Year Four, Originated, Three Years Before Current Fiscal Year	22	18
Gross Principal Charge-off, Year Five, Originated, Four Years Before Current Fiscal Year	8	9
Gross Principal Charge-off Originated More Than Five Years Before Current Fiscal Year	7	11
Financing Receivable, Allowance for Credit Loss, Writeoff	$ 113	$ 54

Loan Receivables (Schedule of_3

Loan Receivables (Schedule of Delinquent and Non-Accruing Loans) (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Financing Receivable, Past Due [Line Items]
Loan receivables		$ 126,555		$ 128,409
Loan receivables, 90 or more days delinquent and accruing		2,017		1,990
Loan receivables, total non-accruing	[1]	278		269
30-89 Days Delinquent [Member]
Financing Receivable, Past Due [Line Items]
Loan receivables		2,203		2,382
90 or More Days Delinquent [Member]
Financing Receivable, Past Due [Line Items]
Loan receivables		2,079		2,045
Total Past Due [Member]
Financing Receivable, Past Due [Line Items]
Loan receivables		4,282		4,427
Credit Card Loans [Member]
Financing Receivable, Past Due [Line Items]
Loan receivables	[2],[3]	99,475		102,259
Loan receivables, 90 or more days delinquent and accruing		1,900		1,881
Loan receivables, total non-accruing	[1]	203		197
Estimated gross interest income that would have been recorded based on original terms		9	$ 8
Credit Card Loans [Member] | 30-89 Days Delinquent [Member]
Financing Receivable, Past Due [Line Items]
Loan receivables, credit card		1,869		2,038
Credit Card Loans [Member] | 90 or More Days Delinquent [Member]
Financing Receivable, Past Due [Line Items]
Loan receivables, credit card		1,941		1,917
Credit Card Loans [Member] | Total Past Due [Member]
Financing Receivable, Past Due [Line Items]
Loan receivables, credit card		3,810		3,955
Total Other Loans [Member]
Financing Receivable, Past Due [Line Items]
Loan receivables	[4]	27,080		26,150
Loan receivables, 90 or more days delinquent and accruing		117		109
Loan receivables, total non-accruing	[1]	75		72
Total Other Loans [Member] | 30-89 Days Delinquent [Member]
Financing Receivable, Past Due [Line Items]
Loan receivables		334		344
Total Other Loans [Member] | 90 or More Days Delinquent [Member]
Financing Receivable, Past Due [Line Items]
Loan receivables		138		128
Total Other Loans [Member] | Total Past Due [Member]
Financing Receivable, Past Due [Line Items]
Loan receivables		472		472
Total Other Loans [Member] | Private Student Loans [Member]
Financing Receivable, Past Due [Line Items]
Loan receivables	[4],[5]	10,480		10,352
Loan receivables, 90 or more days delinquent and accruing		77		69
Loan receivables, total non-accruing	[1]	8		8
Total Other Loans [Member] | Private Student Loans [Member] | 30-89 Days Delinquent [Member]
Financing Receivable, Past Due [Line Items]
Loan receivables	[6]	193		201
Total Other Loans [Member] | Private Student Loans [Member] | 90 or More Days Delinquent [Member]
Financing Receivable, Past Due [Line Items]
Loan receivables	[6]	78		70
Total Other Loans [Member] | Private Student Loans [Member] | Total Past Due [Member]
Financing Receivable, Past Due [Line Items]
Loan receivables	[6]	271		271
Total Other Loans [Member] | Personal Loans [Member]
Financing Receivable, Past Due [Line Items]
Loan receivables	[4]	10,107		9,852
Loan receivables, 90 or more days delinquent and accruing		37		37
Loan receivables, total non-accruing	[1]	11		11
Total Other Loans [Member] | Personal Loans [Member] | 30-89 Days Delinquent [Member]
Financing Receivable, Past Due [Line Items]
Loan receivables		108		104
Total Other Loans [Member] | Personal Loans [Member] | 90 or More Days Delinquent [Member]
Financing Receivable, Past Due [Line Items]
Loan receivables		39		39
Total Other Loans [Member] | Personal Loans [Member] | Total Past Due [Member]
Financing Receivable, Past Due [Line Items]
Loan receivables		147		143
Total Other Loans [Member] | Other Loans [Member]
Financing Receivable, Past Due [Line Items]
Loan receivables	[4]	6,493		5,946
Loan receivables, 90 or more days delinquent and accruing		3		3
Loan receivables, total non-accruing	[1]	56		53
Total Other Loans [Member] | Other Loans [Member] | 30-89 Days Delinquent [Member]
Financing Receivable, Past Due [Line Items]
Loan receivables		33		39
Total Other Loans [Member] | Other Loans [Member] | 90 or More Days Delinquent [Member]
Financing Receivable, Past Due [Line Items]
Loan receivables		21		19
Total Other Loans [Member] | Other Loans [Member] | Total Past Due [Member]
Financing Receivable, Past Due [Line Items]
Loan receivables		$ 54		$ 58
[1] The Company estimates that the gross interest income that would have been recorded under the original terms of non-accruing credit card loans was $9 million and $8 million for the three months ended March 31, 2024 and 2023, respectively. The Company does not separately track the amount of gross interest income that would have been recorded under the original terms of loans. Instead, the Company estimated this amount based on customers' current balances and most recent interest rates. Amounts include carrying values of $13.9 billion and $14.8 billion underlying investors' interest in trust debt at March 31, 2024 and December 31, 2023, respectively, and $15.2 billion and $15.6 billion in seller's interest at March 31, 2024 and December 31, 2023, respectively. See Note 4: Credit Card and Private Student Loan Securitization Activities for additional information. Unbilled accrued interest receivable on credit card loans, which is presented as part of other assets in the Company's condensed consolidated statements of financial condition, was $746 million and $753 million at March 31, 2024 and December 31, 2023, respectively. Accrued interest receivable on private student, personal and other loans, which is presented as part of other assets in the Company's condensed consolidated statements of financial condition, was $555 million, $72 million and $23 million, respectively, at March 31, 2024 and $522 million, $69 million and $21 million, respectively, at December 31, 2023. Private student loans may include a deferment period, during which borrowers are not required to make payments while enrolled in school at least half time as determined by the school. During a deferment period, these loans do not advance into delinquency.

Loan Receivables (Schedule of_4

Loan Receivables (Schedule of Loans That Entered a Modification Program During the Period) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024		Mar. 31, 2023
Credit Card Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 920	[1]	$ 632
Financing Receivable, Modified in Period, to Total Financing Receivables, Percentage	0.92%	[1]	0.70%
Financing Receivable, Revolving, Converted to Term Loan During Period	$ 185		$ 118
Credit Card Loans [Member] | Contractual Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Troubled Debt Restructuring, Postmodification	920	[1]	632
Total Other Loans [Member] | Private Student Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 102		$ 32
Financing Receivable, Modified in Period, to Total Financing Receivables, Percentage	0.97%		0.04%
Total Other Loans [Member] | Private Student Loans [Member] | Payment Deferral
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 1		$ 3
Total Other Loans [Member] | Private Student Loans [Member] | InterestRateReductionandPaymentDeferral
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Troubled Debt Restructuring, Postmodification	101		29
Total Other Loans [Member] | Personal Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 54		$ 30
Financing Receivable, Modified in Period, to Total Financing Receivables, Percentage	0.53%		0.36%
Total Other Loans [Member] | Personal Loans [Member] | Payment Deferral
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 4		$ 2
Total Other Loans [Member] | Personal Loans [Member] | InterestRateReductionandPaymentDeferral
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Troubled Debt Restructuring, Postmodification	26		14
Total Other Loans [Member] | Personal Loans [Member] | Extended Maturity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Troubled Debt Restructuring, Postmodification	10		8
Total Other Loans [Member] | Personal Loans [Member] | Extended Maturity and Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 14		$ 6
[1]Accounts that entered a credit card loan modification program include $185 million and $118 million that were converted from revolving line-of-credit arrangements to term loans during the three months ended March 31, 2024 and 2023, respectively.

Loan Receivables (Schedule of_5

Loan Receivables (Schedule of Loan Modification Effects) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Credit Card Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Modified, Weighted Average Interest Rate Decrease from Modification	14.42%	13.38%
Interest and fees forgiven due to loan modification program	$ 56	$ 12
Credit Card Loans [Member] | Principal Forgiveness
Accounts, Notes, Loans and Financing Receivable [Line Items]
FinancingReceivableExcludingAccruedInterestModifiedPeriod	$ 56
Total Other Loans [Member] | Private Student Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Modified, Weighted Average Interest Rate Decrease from Modification	8.84%	8.02%
Total Other Loans [Member] | Private Student Loans [Member] | Minimum [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Payment delay duration (in months)	6 months	6 months
Total Other Loans [Member] | Private Student Loans [Member] | Maximum [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Payment delay duration (in months)	12 months	12 months
Total Other Loans [Member] | Personal Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Modified, Weighted Average Interest Rate Decrease from Modification	13.20%	11.55%
Financing Receivable, Modified, Weighted Average Term Increase from Modification	40 months	38 months
Total Other Loans [Member] | Personal Loans [Member] | Minimum [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Payment delay duration (in months)	6 months	6 months
Total Other Loans [Member] | Personal Loans [Member] | Maximum [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Payment delay duration (in months)	12 months	12 months

Loan Receivables (Schedule of_6

Loan Receivables (Schedule of Delinquent Loans Receivables Aging) (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Financial Asset, 1 to 29 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing Receivable, Troubled Debt Restructuring	$ 2,451	$ 2,138
30-89 Days Delinquent [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, Troubled Debt Restructuring	302	290
90 or More Days Delinquent [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, Troubled Debt Restructuring	229	208
Credit Card Loans [Member] | Financial Asset, 1 to 29 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing Receivable, Troubled Debt Restructuring	2,118	1,882
Credit Card Loans [Member] | 30-89 Days Delinquent [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, Troubled Debt Restructuring	257	252
Credit Card Loans [Member] | 90 or More Days Delinquent [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, Troubled Debt Restructuring	217	196
Total Other Loans [Member] | Private Student Loans [Member] | Financial Asset, 1 to 29 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing Receivable, Troubled Debt Restructuring	207	147
Total Other Loans [Member] | Private Student Loans [Member] | 30-89 Days Delinquent [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, Troubled Debt Restructuring	22	18
Total Other Loans [Member] | Private Student Loans [Member] | 90 or More Days Delinquent [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, Troubled Debt Restructuring	8	8
Total Other Loans [Member] | Personal Loans [Member] | Financial Asset, 1 to 29 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing Receivable, Troubled Debt Restructuring	126	109
Total Other Loans [Member] | Personal Loans [Member] | 30-89 Days Delinquent [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, Troubled Debt Restructuring	23	20
Total Other Loans [Member] | Personal Loans [Member] | 90 or More Days Delinquent [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, Troubled Debt Restructuring	$ 4	$ 4

Loan Receivables (Schedule of F

Loan Receivables (Schedule of Financing Receivable, Modified, Subsequent Default) (Details) $ in Millions	3 Months Ended
	Mar. 31, 2024 USD ($)
Credit Card Loans [Member] | Carrying Value [Member]
Financing Receivable, Modified, Subsequent Default [Line Items]
Defaulted Amount	$ 205
Credit Card Loans [Member]
Financing Receivable, Modified, Subsequent Default [Line Items]
Defaulted Amount	161
Credit Card Loans [Member] | Contractual Interest Rate Reduction | Carrying Value [Member]
Financing Receivable, Modified, Subsequent Default [Line Items]
Defaulted Amount	205
Credit Card Loans [Member] | Contractual Interest Rate Reduction
Financing Receivable, Modified, Subsequent Default [Line Items]
Defaulted Amount	161
Total Other Loans [Member] | Private Student Loans [Member] | Carrying Value [Member]
Financing Receivable, Modified, Subsequent Default [Line Items]
Defaulted Amount	19
Total Other Loans [Member] | Private Student Loans [Member]
Financing Receivable, Modified, Subsequent Default [Line Items]
Defaulted Amount	18
Total Other Loans [Member] | Private Student Loans [Member] | Payment Deferral | Carrying Value [Member]
Financing Receivable, Modified, Subsequent Default [Line Items]
Defaulted Amount	2
Total Other Loans [Member] | Private Student Loans [Member] | Payment Deferral
Financing Receivable, Modified, Subsequent Default [Line Items]
Defaulted Amount	2
Total Other Loans [Member] | Private Student Loans [Member] | InterestRateReductionandPaymentDeferral | Carrying Value [Member]
Financing Receivable, Modified, Subsequent Default [Line Items]
Defaulted Amount	17
Total Other Loans [Member] | Private Student Loans [Member] | InterestRateReductionandPaymentDeferral
Financing Receivable, Modified, Subsequent Default [Line Items]
Defaulted Amount	16
Total Other Loans [Member] | Personal Loans [Member] | Carrying Value [Member]
Financing Receivable, Modified, Subsequent Default [Line Items]
Defaulted Amount	14
Total Other Loans [Member] | Personal Loans [Member]
Financing Receivable, Modified, Subsequent Default [Line Items]
Defaulted Amount	8
Total Other Loans [Member] | Personal Loans [Member] | Payment Deferral | Carrying Value [Member]
Financing Receivable, Modified, Subsequent Default [Line Items]
Defaulted Amount	1
Total Other Loans [Member] | Personal Loans [Member] | Payment Deferral
Financing Receivable, Modified, Subsequent Default [Line Items]
Defaulted Amount	1
Total Other Loans [Member] | Personal Loans [Member] | InterestRateReductionandPaymentDeferral | Carrying Value [Member]
Financing Receivable, Modified, Subsequent Default [Line Items]
Defaulted Amount	7
Total Other Loans [Member] | Personal Loans [Member] | InterestRateReductionandPaymentDeferral
Financing Receivable, Modified, Subsequent Default [Line Items]
Defaulted Amount	3
Total Other Loans [Member] | Personal Loans [Member] | Extended Maturity | Carrying Value [Member]
Financing Receivable, Modified, Subsequent Default [Line Items]
Defaulted Amount	2
Total Other Loans [Member] | Personal Loans [Member] | Extended Maturity
Financing Receivable, Modified, Subsequent Default [Line Items]
Defaulted Amount	1
Total Other Loans [Member] | Personal Loans [Member] | Extended Maturity and Interest Rate Reduction | Carrying Value [Member]
Financing Receivable, Modified, Subsequent Default [Line Items]
Defaulted Amount	4
Total Other Loans [Member] | Personal Loans [Member] | Extended Maturity and Interest Rate Reduction
Financing Receivable, Modified, Subsequent Default [Line Items]
Defaulted Amount	$ 3

Credit Card and Private Stude_3

Credit Card and Private Student Loan Securitization Activities (Narrative) (Details)	3 Months Ended
	Mar. 31, 2024 classes
Variable Interest Entity, Primary Beneficiary [Member] | Discover Card Execution Note Trust [Member] | Credit Card Securitization Trusts [Member]
Variable Interest Entity [Line Items]
Number of classes of securities in debt structure (in classes)	4

Credit Card and Private Stude_4

Credit Card and Private Student Loan Securitization Activities (Schedule of Restricted Credit Card Securitized Assets) (Details) - USD ($) $ in Millions		Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2022
Variable Interest Entity [Line Items]
Restricted cash		$ 439	$ 43	$ 33
Loan receivables		126,555	128,409
Allowance for credit losses allocated to securitized loan receivables		(9,258)	(9,283)	$ (7,691)	$ (7,374)
Net loan receivables		117,297	119,126
Other assets		6,065	5,667
Total assets		152,689	151,522
Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Restricted cash		439	43
Loan receivables		29,192	30,590
Allowance for credit losses allocated to securitized loan receivables		(1,323)	(1,347)
Other assets		4	3
Variable Interest Entity, Primary Beneficiary [Member] | Credit Card Securitization Trusts [Member]
Variable Interest Entity [Line Items]
Restricted cash		432	36
Investors' interests held by third-party investors		10,975	11,725
Investors' interests held by wholly-owned subsidiaries of Discover Bank		2,917	3,117
Seller's interest		15,155	15,598
Loan receivables	[1]	29,047	30,440
Allowance for credit losses allocated to securitized loan receivables	[1]	(1,323)	(1,347)
Net loan receivables		27,724	29,093
Other assets		3	2
Total assets		$ 28,159	$ 29,131
[1] The Company maintains its allowance for credit losses at an amount equal to lifetime expected credit losses associated with all loan receivables, which includes all loan receivables in the trusts. Therefore, the credit risk associated with the transferred receivables is fully reflected on the Company's statements of financial condition in accordance with GAAP.

Deposits (Schedule of Certifica

Deposits (Schedule of Certificates of Deposit Maturities) (Details) $ in Millions	Mar. 31, 2024 USD ($)
Deposits [Abstract]
2024	$ 21,263
2025	12,190
2026	4,211
2027	4,408
2028	2,161
Thereafter	1,009
Total	$ 45,242

Long-Term Borrowings (Narrative

Long-Term Borrowings (Narrative) (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Debt Instrument [Line Items]
Federal Home Loan Bank, advances, general debt obligations, maximum amount available	$ 4,100	$ 3,600
Federal Home Loan Bank advances	1,000	1,000
Discover Card Master Trust I and Discover Card Execution Note Trust [Member] | Securitized Debt [Member]
Debt Instrument [Line Items]
Total commitment of secured credit facilities	3,500	3,500
Total used commitment of secured credit facilities	$ 0	$ 750

Long-Term Borrowings (Schedule

Long-Term Borrowings (Schedule of Long-Term Borrowings and Weighted Average Interest Rates) (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2024	Dec. 31, 2023
Debt Instrument [Line Items]
Long-term borrowings (in dollars)		$ 20,475	$ 20,581
Securitized Debt [Member] | Discover Card Master Trust I and Discover Card Execution Note Trust [Member]
Debt Instrument [Line Items]
Long-term borrowings (in dollars)		$ 10,872	10,928
Securitized Debt [Member] | Discover Card Master Trust I and Discover Card Execution Note Trust [Member] | Fixed-Rate Asset-Backed Securities [Member]
Debt Instrument [Line Items]
Weighted-average interest rate	[1]	3.17%
Long-term borrowings (in dollars)	[1]	$ 9,947	10,003
Securitized Debt [Member] | Discover Card Master Trust I and Discover Card Execution Note Trust [Member] | Fixed-Rate Asset-Backed Securities [Member] | Minimum [Member]
Debt Instrument [Line Items]
Interest rate	[1]	0.58%
Securitized Debt [Member] | Discover Card Master Trust I and Discover Card Execution Note Trust [Member] | Fixed-Rate Asset-Backed Securities [Member] | Maximum [Member]
Debt Instrument [Line Items]
Interest rate	[1]	5.03%
Securitized Debt [Member] | Discover Card Master Trust I and Discover Card Execution Note Trust [Member] | Floating-Rate Asset-Backed Securities [Member]
Debt Instrument [Line Items]
Weighted-average interest rate	[2]	6.04%
Long-term borrowings (in dollars)	[2]	$ 925	925
Securitized Debt [Member] | Discover Card Master Trust I and Discover Card Execution Note Trust [Member] | Floating-Rate Asset-Backed Securities [Member] | 1-Month SOFR [Member]
Debt Instrument [Line Items]
Interest rate terms		1-month Term SOFR + 0.11448% Tenor Spread Adjustment + 60 basis points
Securitized Debt [Member] | Discover Card Master Trust I and Discover Card Execution Note Trust [Member] | Floating-Rate Asset-Backed Securities [Member] | Minimum [Member]
Debt Instrument [Line Items]
Interest rate	[2]	6.04%
Securitized Debt [Member] | Discover Card Master Trust I and Discover Card Execution Note Trust [Member] | Floating-Rate Asset-Backed Securities [Member] | Minimum [Member] | 1-Month SOFR [Member]
Debt Instrument [Line Items]
Basis spread on variable rate		0.60%
Securitized Debt [Member] | Discover Card Master Trust I and Discover Card Execution Note Trust [Member] | Floating-Rate Asset-Backed Securities [Member] | Maximum [Member]
Debt Instrument [Line Items]
Interest rate		6.04%
Securitized Debt [Member] | Student Loan Trust [Member]
Debt Instrument [Line Items]
Long-term borrowings (in dollars)		$ 61	65
Securitized Debt [Member] | Student Loan Trust [Member] | Floating-Rate Asset-Backed Securities [Member]
Debt Instrument [Line Items]
Weighted-average interest rate	[3],[4]	9.50%
Long-term borrowings (in dollars)	[3],[4]	$ 61	65
Securitized Debt [Member] | Student Loan Trust [Member] | Floating-Rate Asset-Backed Securities [Member] | Prime Rate [Member]
Debt Instrument [Line Items]
Interest rate terms		Prime rate + 100 basis points
Basis spread on variable rate		1%
Securitized Debt [Member] | Student Loan Trust [Member] | Floating-Rate Asset-Backed Securities [Member] | Minimum [Member]
Debt Instrument [Line Items]
Interest rate		9.50%
Securitized Debt [Member] | Student Loan Trust [Member] | Floating-Rate Asset-Backed Securities [Member] | Maximum [Member]
Debt Instrument [Line Items]
Interest rate	[3],[4]	9.50%
Securitized Debt [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Debt Instrument [Line Items]
Long-term borrowings (in dollars)		$ 10,933	10,993
Securitized Debt [Member] | Discover Bank [Member] | Floating-Rate Asset-Backed Securities [Member] | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate [Member]
Debt Instrument [Line Items]
Interest rate terms		SOFR plus a spread ranging from 16 to 26 basis points
Corporate Debt Securities [Member] | Parent Company [Member] | Fixed-Rate Senior Notes [Member]
Debt Instrument [Line Items]
Weighted-average interest rate		4.68%
Long-term borrowings (in dollars)		$ 3,337	3,336
Corporate Debt Securities [Member] | Parent Company [Member] | Fixed-Rate Senior Notes [Member] | Minimum [Member]
Debt Instrument [Line Items]
Interest rate		3.75%
Corporate Debt Securities [Member] | Parent Company [Member] | Fixed-Rate Senior Notes [Member] | Maximum [Member]
Debt Instrument [Line Items]
Interest rate		6.70%
Corporate Debt Securities [Member] | Parent Company [Member] | Fixed-Rate Retail Notes [Member]
Debt Instrument [Line Items]
Weighted-average interest rate		3.82%
Long-term borrowings (in dollars)		$ 139	140
Corporate Debt Securities [Member] | Parent Company [Member] | Fixed-Rate Retail Notes [Member] | Minimum [Member]
Debt Instrument [Line Items]
Interest rate		3.25%
Corporate Debt Securities [Member] | Parent Company [Member] | Fixed-Rate Retail Notes [Member] | Maximum [Member]
Debt Instrument [Line Items]
Interest rate		4.40%
Corporate Debt Securities [Member] | Parent Company [Member] | Fixed to Floating-Rate Senior Notes
Debt Instrument [Line Items]
Weighted-average interest rate		7.96%
Long-term borrowings (in dollars)		$ 992	993
Corporate Debt Securities [Member] | Parent Company [Member] | Fixed to Floating-Rate Senior Notes | Minimum [Member]
Debt Instrument [Line Items]
Interest rate		7.96%
Corporate Debt Securities [Member] | Parent Company [Member] | Fixed to Floating-Rate Senior Notes | Maximum [Member]
Debt Instrument [Line Items]
Interest rate		7.96%
Corporate Debt Securities [Member] | Parent | Fixed to Floating-Rate Senior Notes | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate [Member]
Debt Instrument [Line Items]
Interest rate terms		SOFR + 3.370%
Senior Notes [Member] | Discover Bank [Member] | Fixed-Rate Senior Bank Notes [Member]
Debt Instrument [Line Items]
Weighted-average interest rate	[1]	3.53%
Long-term borrowings (in dollars)	[1]	$ 3,535	3,571
Senior Notes [Member] | Discover Bank [Member] | Fixed-Rate Senior Bank Notes [Member] | Minimum [Member]
Debt Instrument [Line Items]
Interest rate	[1]	2.45%
Senior Notes [Member] | Discover Bank [Member] | Fixed-Rate Senior Bank Notes [Member] | Maximum [Member]
Debt Instrument [Line Items]
Interest rate	[1]	4.65%
Subordinated Debt [Member] | Discover Bank [Member] | Fixed-Rate Subordinated Bank Notes
Debt Instrument [Line Items]
Weighted-average interest rate	[1]	5.97%
Long-term borrowings (in dollars)	[1]	$ 491	500
Subordinated Debt [Member] | Discover Bank [Member] | Fixed-Rate Subordinated Bank Notes | Minimum [Member]
Debt Instrument [Line Items]
Interest rate		5.97%
Subordinated Debt [Member] | Discover Bank [Member] | Fixed-Rate Subordinated Bank Notes | Maximum [Member]
Debt Instrument [Line Items]
Interest rate	[1]	5.97%
Federal Home Loan Bank Advances | Discover Bank [Member] | Minimum [Member] | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate [Member]
Debt Instrument [Line Items]
Basis spread on variable rate		0.16%
Federal Home Loan Bank Advances | Discover Bank [Member] | Maximum [Member] | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate [Member]
Debt Instrument [Line Items]
Basis spread on variable rate		0.26%
Federal Home Loan Bank Advances | Discover Bank [Member] | Fixed-Rate FHLB Advance
Debt Instrument [Line Items]
Weighted-average interest rate		4.82%
Long-term borrowings (in dollars)		$ 523	523
Federal Home Loan Bank Advances | Discover Bank [Member] | Fixed-Rate FHLB Advance | Minimum [Member]
Debt Instrument [Line Items]
Interest rate		4.77%
Federal Home Loan Bank Advances | Discover Bank [Member] | Fixed-Rate FHLB Advance | Maximum [Member]
Debt Instrument [Line Items]
Interest rate		4.82%
Federal Home Loan Bank Advances | Discover Bank [Member] | Floating-Rate FHLB Advance
Debt Instrument [Line Items]
Weighted-average interest rate		5.59%
Long-term borrowings (in dollars)		$ 525	$ 525
Federal Home Loan Bank Advances | Discover Bank [Member] | Floating-Rate FHLB Advance | Minimum [Member]
Debt Instrument [Line Items]
Interest rate		5.49%
Federal Home Loan Bank Advances | Discover Bank [Member] | Floating-Rate FHLB Advance | Maximum [Member]
Debt Instrument [Line Items]
Interest rate		5.59%
[1] The Company uses interest rate swaps to hedge portions of these long-term borrowings against changes in fair value attributable to changes in the applicable benchmark interest rates. The use of these interest rate swaps impacts the carrying value of the debt. See Note 15: Derivatives and Hedging Activities. DCENT floating-rate asset-backed securities include issuances with the following interest rate terms: 1-month Term SOFR + 0.11448% Tenor Spread Adjustment + 60 basis points as of March 31, 2024. Repayment of this debt is dependent upon the timing of principal and interest payments on the underlying private student loans. The date shown represents the final maturity date. (5) The fixed to floating-rate senior notes include a rate reset on November 2, 2033, to a floating rate based on compounded SOFR + 3.370%. (6) The floating-rate FHLB advances include interest rate terms based on SOFR plus a spread ranging from 16 to 26 basis points as of March 31, 2024. The private student loan securitization trust floating-rate asset-backed security includes an issuance with the following interest rate term: Prime rate + 100 basis points as of March 31, 2024.

Long-Term Borrowings (Schedul_2

Long-Term Borrowings (Schedule of Long-Term Borrowings Maturities) (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Debt Disclosure [Abstract]
2024	$ 4,250
2025	6,121
2026	4,868
2027	1,001
2028	1,412
Thereafter	2,823
Total	$ 20,475	$ 20,581

Preferred Stock (Schedule of St

Preferred Stock (Schedule of Stock by Class) (Details) - USD ($) $ / shares in Units, $ in Millions				3 Months Ended
		Jun. 22, 2020	Oct. 31, 2017	Mar. 31, 2024	Dec. 31, 2023
Class of Stock [Line Items]
Preferred stock, par or stated value per share				$ 0.01	$ 0.01
Series C Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock, initial issue date	[1]		Oct. 31, 2017
Preferred stock, earliest redemption date				Oct. 30, 2027
Series D Preferred Stock
Class of Stock [Line Items]
Preferred stock, initial issue date	[1]	Jun. 22, 2020
Dividend rate reset				5 years
Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock, depositary shares issued (in number of depositary shares)				1,070,000	1,070,000
Proceeds from issuance of preferred stock, net				$ 1,056	$ 1,056
Preferred Stock [Member] | Series C Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock, liquidation preference per share	[1],[2],[3]			$ 1,000
Preferred stock, redemption price per share	[1],[2],[3]			$ 1,000
Preferred Stock, Dividend Rate, Percentage	[1],[4]			5.50%
Preferred stock, depositary shares issued (in number of depositary shares)	[1]			570,000	570,000
Proceeds from issuance of preferred stock, net	[1]			$ 563	$ 563
Depositary shares represented by one preferred share				100
Preferred stock, par or stated value per share				$ 0.01
Redemption period of preferred stock following regulatory capital treatment event				90 days
Preferred stock dividend payment rate variable, rate to be used in future periods				3%
Preferred Stock [Member] | Series C Preferred Stock [Member] | Three-Month Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate
Class of Stock [Line Items]
Preferred stock dividend payment rate variable, rate to be used in future periods				0.03338
Preferred Stock [Member] | Series D Preferred Stock
Class of Stock [Line Items]
Preferred stock, liquidation preference per share	[1],[3],[5]			$ 1,000
Preferred stock, redemption price per share	[1],[3],[5]			$ 1,000
Preferred Stock, Dividend Rate, Percentage	[1],[6]			6.125%
Preferred stock, depositary shares issued (in number of depositary shares)	[1]			500,000	500,000
Proceeds from issuance of preferred stock, net	[1]			$ 493	$ 493
Depositary shares represented by one preferred share				100
Preferred stock, par or stated value per share				$ 0.01
Redemption period of preferred stock following regulatory capital treatment event				90 days
Preferred stock dividend payment rate variable, rate to be used in future periods				5%
Preferred Stock [Member] | Series D Preferred Stock | Five-Year Treasury Rate
Class of Stock [Line Items]
Preferred stock dividend payment rate variable, rate to be used in future periods				0.05783
[1] Issued as depositary shares, each representing 1/100 th interest in a share of the corresponding series of preferred stock. Each preferred share has a par value of $0.01. Redeemable at the Company’s option, subject to regulatory approval, either (i) in whole or in part on any dividend payment date on or after October 30, 2027, or (ii) in whole but not in part, at any time within 90 days following a regulatory capital treatment event (as defined in the certificate of designations for the Series C preferred stock). Redeemable at the redemption price plus declared and unpaid dividends. Any dividends declared are payable semi-annually in arrears at a rate of 5.500% per annum until October 30, 2027. Thereafter, dividends declared will be payable quarterly in arrears at a floating rate equal to 3-month Term SOFR plus a spread of 3.338% per annum. Redeemable at the Company’s option, subject to regulatory approval, either (i) in whole or in part during the three-month period prior to, and including, each reset date (as defined in the certificate of designations for the Series D preferred stock) or (ii) in whole but not in part, at any time within 90 days following a regulatory capital treatment event (as defined in the certificate of designations for the Series D Preferred Stock). Any dividends declared are payable semi-annually in arrears at a rate of 6.125% per annum until September 23, 2025, after which the dividend rate will reset every 5 years to a fixed annual rate equal to the 5-year Treasury plus a spread of 5.783%.

Accumulated Other Comprehensi_3

Accumulated Other Comprehensive Income (Schedule of Changes in Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss), net of tax, balance at beginning of period	$ (225)
Net change in accumulated other comprehensive income (loss), net of tax	(168)	$ 104
Accumulated other comprehensive income (loss), net of tax, balance at end of period	(393)
Unrealized Gains (Losses) on Available-for-Sale Investment Securities, Net of Tax [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss), net of tax, balance at beginning of period	(37)	(136)
Net change in accumulated other comprehensive income (loss), net of tax	(97)	92
Accumulated other comprehensive income (loss), net of tax, balance at end of period	(134)	(44)
Gains (Losses) on Cash Flow Hedges, Net of Tax [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss), net of tax, balance at beginning of period	(8)	(14)
Net change in accumulated other comprehensive income (loss), net of tax	(71)	12
Accumulated other comprehensive income (loss), net of tax, balance at end of period	(79)	(2)
Gains (Losses) on Pension Plan, Net of Tax [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss), net of tax, balance at beginning of period	(180)	(189)
Net change in accumulated other comprehensive income (loss), net of tax	0	0
Accumulated other comprehensive income (loss), net of tax, balance at end of period	(180)	(189)
Accumulated Other Comprehensive (Loss) Income [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss), net of tax, balance at beginning of period	(225)	(339)
Net change in accumulated other comprehensive income (loss), net of tax	(168)	104
Accumulated other comprehensive income (loss), net of tax, balance at end of period	$ (393)	$ (235)

Accumulated Other Comprehensi_4

Accumulated Other Comprehensive Income (Schedule of Other Comprehensive Income Before Reclassifications and Amounts Reclassified from AOCI) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Available-for-sale investment securities, net unrealized holding gains (losses) arising during the period, before tax	$ (129)	$ 122
Available-for-sale investment securities, net unrealized holding gains (losses) arising during the period, tax benefit (expense)	32	(30)
Available-for-sale investment securities, net unrealized holding gains (losses) arising during the period, net of tax	(97)	92
Available-for-sale investment securities, net change, before tax	(129)	122
Available-for-sale investment securities, net change, tax benefit (expense)	32	(30)
Available-for-sale investment securities, net change, net of tax	(97)	92
Cash flow hedges, net unrealized gains (losses) arising during the period, before tax	(131)	10
Cash flow hedges, net unrealized gains (losses) arising during the period, tax benefit (expense)	32	(2)
Cash flow hedges, net unrealized gains (losses) arising during the period, net of tax	(99)	8
Cash flow hedges, amounts reclassified from AOCI, before tax	37	5
Cash flow hedges, amounts reclassified from AOCI, tax benefit (expense)	(9)	(1)
Cash flow hedges, amounts reclassified from AOCI, net of tax	28	4
Cash flow hedges, net change, before tax	(94)	15
Cash flow hedges, net change, tax benefit (expense)	23	(3)
Cash flow hedges, net change, net of tax	$ (71)	$ 12

Income Taxes (Schedule of Effec

Income Taxes (Schedule of Effective Income Tax Rate Calculation) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Income Tax Disclosure [Abstract]
Income before income taxes	$ 404	$ 1,257
Income tax expense	$ 96	$ 289
Effective income tax rate (in percent)	23.70%	23%

Earnings Per Share (Schedule of

Earnings Per Share (Schedule of Basic and Diluted EPS ) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Numerator:
Net income	$ 308	$ 968
Preferred stock dividends	(31)	(31)
Net income available to common stockholders	277	937
Income allocated to participating securities	(3)	(6)
Net income allocated to common stockholders	274	931
Net income (loss) available to common stockholders, diluted	$ 274	$ 931
Denominator:
Weighted-average shares of common stock outstanding	250	262
Weighted-average shares of common stock outstanding and common stock equivalents	250	262
Basic earnings per common share (in dollars per share)	$ 1.10	$ 3.55
Diluted earnings per common share (in dollars per share)	$ 1.10	$ 3.55

Capital Adequacy (Schedule of M

Capital Adequacy (Schedule of Minimum and Well-Capitalized Requirements) (Details) $ in Millions		Mar. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Parent Company [Member]
Compliance with Regulatory Capital Requirements [Line Items]
Total capital to risk-weighted assets, actual amount		$ 17,513	$ 17,986
Total capital to risk-weighted assets, actual ratio (in percent)	[1]	0.133	0.137
Total capital to risk-weighted assets, minimum capital requirements, amount		$ 10,499	$ 10,471
Total capital to risk-weighted assets, minimum capital requirements, ratio (in percent)		0.080	0.080
Total capital to risk-weighted assets, capital requirements to be classified as well-capitalized, amount	[2]	$ 13,124	$ 13,088
Total capital to risk-weighted assets, capital requirements to be classified as well-capitalized, ratio (in percent)	[2]	0.100	0.100
Tier I capital to risk-weighted assets, actual amount		$ 15,394	$ 15,872
Tier I capital to risk-weighted assets, actual ratio (in percent)	[1]	0.117	0.121
Tier I capital to risk-weighted assets, minimum capital requirements, amount		$ 7,874	$ 7,853
Tier I capital to risk-weighted assets, minimum capital requirements, ratio (in percent)		0.060	0.060
Tier I capital to risk-weighted assets, capital requirements to be classified as well-capitalized, amount	[2]	$ 7,874	$ 7,853
Tier I capital to risk-weighted assets, capital requirements to be classified as well-capitalized, ratio (in percent)	[2]	0.060	0.060
Tier I capital to average assets, actual amount		$ 15,394	$ 15,872
Tier I capital to average assets, actual ratio (in percent)	[1]	0.101	0.107
Tier I capital to average assets, minimum capital requirements, amount		$ 6,086	$ 5,915
Tier I capital to average assets, minimum capital requirements, ratio (in percent)		0.040	0.040
CET1 capital to risk-weighted assets, actual amount		$ 14,338	$ 14,816
CET1 capital to risk-weighted assets, actual ratio (in percent)	[1]	0.109	0.113
CET1 capital to risk-weighted assets, minimum capital requirements, amount		$ 5,906	$ 5,890
CET1 capital to risk-weighted assets, minimum capital requirements, ratio (in percent)		4.50%	4.50%
Discover Bank [Member]
Compliance with Regulatory Capital Requirements [Line Items]
Total capital to risk-weighted assets, actual amount		$ 16,598	$ 16,856
Total capital to risk-weighted assets, actual ratio (in percent)	[1]	0.128	0.130
Total capital to risk-weighted assets, minimum capital requirements, amount		$ 10,349	$ 10,352
Total capital to risk-weighted assets, minimum capital requirements, ratio (in percent)		0.080	0.080
Total capital to risk-weighted assets, capital requirements to be classified as well-capitalized, amount	[2]	$ 12,936	$ 12,939
Total capital to risk-weighted assets, capital requirements to be classified as well-capitalized, ratio (in percent)	[2]	0.100	0.100
Tier I capital to risk-weighted assets, actual amount		$ 13,752	$ 13,910
Tier I capital to risk-weighted assets, actual ratio (in percent)	[1]	0.106	0.108
Tier I capital to risk-weighted assets, minimum capital requirements, amount		$ 7,762	$ 7,764
Tier I capital to risk-weighted assets, minimum capital requirements, ratio (in percent)		0.060	0.060
Tier I capital to risk-weighted assets, capital requirements to be classified as well-capitalized, amount	[2]	$ 10,349	$ 10,352
Tier I capital to risk-weighted assets, capital requirements to be classified as well-capitalized, ratio (in percent)	[2]	0.080	0.080
Tier I capital to average assets, actual amount		$ 13,752	$ 13,910
Tier I capital to average assets, actual ratio (in percent)	[1]	0.092	0.095
Tier I capital to average assets, minimum capital requirements, amount		$ 6,004	$ 5,833
Tier I capital to average assets, minimum capital requirements, ratio (in percent)		0.040	0.040
Tier I capital to average assets, capital requirements to be classified as well-capitalized, amount	[2]	$ 7,505	$ 7,292
Tier I capital to average assets, capital requirements to be classified as well-capitalized, ratio (in percent)	[2]	0.050	0.050
CET1 capital to risk-weighted assets, actual amount		$ 13,752	$ 13,910
CET1 capital to risk-weighted assets, actual ratio (in percent)	[1]	0.106	0.108
CET1 capital to risk-weighted assets, minimum capital requirements, amount		$ 5,821	$ 5,823
CET1 capital to risk-weighted assets, minimum capital requirements, ratio (in percent)		4.50%	4.50%
CET1 capital to risk-weighted assets, capital requirements to be classified as well-capitalized, amount	[2]	$ 8,409	$ 8,411
CET1 capital to risk-weighted assets, capital requirements to be classified as well-capitalized, ratio (in percent)	[2]	6.50%	6.50%
[1] Capital ratios are calculated based on the Basel III standardized approach rules, subject to applicable transition provisions, including CECL transition provisions. The Basel III rules do not establish well-capitalized thresholds for these measures for bank holding companies. Existing well-capitalized thresholds established in the Federal Reserve's Regulation Y have been included where available.

Commitments, Contingencies an_3

Commitments, Contingencies and Guarantees (Narrative) (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Commitments, Contingencies and Guarantees [Line Items]
Off-Balance-Sheet, Credit Loss, Liability	$ 0
Contingent liabilities related to equity method investments	0	$ 0
Commitments to Extend Credit [Member]
Commitments, Contingencies and Guarantees [Line Items]
Unused commitments to extend credit for loans	233,000
CounterpartySettlementGuarantees
Commitments, Contingencies and Guarantees [Line Items]
Guarantor obligations, maximum exposure, undiscounted	110
Merchant Chargeback Guarantees [Member]
Commitments, Contingencies and Guarantees [Line Items]
Escrow deposits and settlement withholdings	$ 9	$ 10

Commitments, Contingencies an_4

Commitments, Contingencies and Guarantees (Schedule of Maximum Potential Counterparty Exposures Related to Settlement Guarantees and Merchant Chargeback Guarantee) (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2024	Mar. 31, 2023
Merchant Chargeback Guarantees [Member]
Loss Contingencies [Line Items]
Aggregate sales transaction volume	[1]	$ 61,332	$ 60,833
[1] Represents transactions processed on the Discover Network for which a potential liability exists that, in aggregate, can differ from credit card sales volume.

Litigation and Regulatory Mat_2

Litigation and Regulatory Matters (Narrative) (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
	Dec. 22, 2020	Mar. 31, 2024	Dec. 31, 2023	Dec. 31, 2023	Jun. 30, 2023
Card Product Misclassification
Loss Contingencies [Line Items]
Accrued Liabilities and Other Liabilities		$ 1,200	$ 375	$ 375	$ 365
Increase in Accrued Merchant Refund Liability			$ 11
Decrease in Accrued Merchant Refund Liability				$ 12
Payments for Legal Settlements		9
Unfavorable Regulatory Action [Member] | Consumer Financial Protection Bureau Consent Order [Member]
Loss Contingencies [Line Items]
Amount of civil money penalty for consent order	$ 25
Maximum [Member] | Pending and Threatened Litigation [Member]
Loss Contingencies [Line Items]
Loss contingency, range of possible loss, portion not accrued		$ 230
Minimum [Member] | Unfavorable Regulatory Action [Member] | Consumer Financial Protection Bureau Consent Order [Member]
Loss Contingencies [Line Items]
Loss contingency, estimate of possible loss	$ 10

Fair Value Measurements (Schedu

Fair Value Measurements (Schedule of Assets and Liabilities Measured at Fair Value on a Recurring Basis) (Details) - USD ($) $ in Millions		Mar. 31, 2024		Dec. 31, 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investment securities, fair value	[1]	$ 13,261		$ 13,402
US Treasury and Government
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investment securities, fair value	[1]	12,822		12,937
Residential Mortgage-Backed Securities - Agency [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investment securities, fair value	[1]	439	[2]	465
Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investment securities, fair value		13,261		13,402
Equity Securities, FV-NI				1
Fair Value, Recurring [Member] | Interest Rate Swaps [Member] | Cash Flow Hedging [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative financial instruments, assets, fair value		1	[3]	2
Derivative financial instruments, liabilities, fair value	[3]	6
Fair Value, Recurring [Member] | Interest Rate Swaps [Member] | Fair Value Hedging [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative financial instruments, assets, fair value				2
Derivative financial instruments, liabilities, fair value		5
Fair Value, Recurring [Member] | US Treasury and Government
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investment securities, fair value		12,822		12,937
Fair Value, Recurring [Member] | Residential Mortgage-Backed Securities - Agency [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investment securities, fair value		439		465
Fair Value, Recurring [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investment securities, fair value		12,815		12,928
Equity Securities, FV-NI				1
Fair Value, Recurring [Member] | Level 1 [Member] | Interest Rate Swaps [Member] | Cash Flow Hedging [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative financial instruments, assets, fair value		0	[3]	0
Derivative financial instruments, liabilities, fair value	[3]	0
Fair Value, Recurring [Member] | Level 1 [Member] | Interest Rate Swaps [Member] | Fair Value Hedging [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative financial instruments, assets, fair value				0
Derivative financial instruments, liabilities, fair value		0
Fair Value, Recurring [Member] | Level 1 [Member] | US Treasury and Government
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investment securities, fair value		12,815		12,928
Fair Value, Recurring [Member] | Level 1 [Member] | Residential Mortgage-Backed Securities - Agency [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investment securities, fair value		0		0
Fair Value, Recurring [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investment securities, fair value		446		474
Equity Securities, FV-NI				0
Fair Value, Recurring [Member] | Level 2 [Member] | Interest Rate Swaps [Member] | Cash Flow Hedging [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative financial instruments, assets, fair value		1	[3]	2
Derivative financial instruments, liabilities, fair value	[3]	6
Fair Value, Recurring [Member] | Level 2 [Member] | Interest Rate Swaps [Member] | Fair Value Hedging [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative financial instruments, assets, fair value				2
Derivative financial instruments, liabilities, fair value		5
Fair Value, Recurring [Member] | Level 2 [Member] | US Treasury and Government
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investment securities, fair value		7		9
Fair Value, Recurring [Member] | Level 2 [Member] | Residential Mortgage-Backed Securities - Agency [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investment securities, fair value		439		465
Fair Value, Recurring [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investment securities, fair value		0		0
Equity Securities, FV-NI				0
Fair Value, Recurring [Member] | Level 3 [Member] | Interest Rate Swaps [Member] | Cash Flow Hedging [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative financial instruments, assets, fair value		0	[3]	0
Derivative financial instruments, liabilities, fair value	[3]	0
Fair Value, Recurring [Member] | Level 3 [Member] | Interest Rate Swaps [Member] | Fair Value Hedging [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative financial instruments, assets, fair value				0
Derivative financial instruments, liabilities, fair value		0
Fair Value, Recurring [Member] | Level 3 [Member] | US Treasury and Government
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investment securities, fair value		0		0
Fair Value, Recurring [Member] | Level 3 [Member] | Residential Mortgage-Backed Securities - Agency [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investment securities, fair value		$ 0		$ 0
[1] Available-for-sale investment securities are reported at fair value. Maturities of RMBS are reflective of the contractual maturities of the investment. Derivative instrument carrying values in an asset or liability position are presented as part of other assets or accrued expenses and other liabilities, respectively, in the Company's condensed consolidated statements of financial condition.

Fair Value Measurements (Narrat

Fair Value Measurements (Narrative) (Details) - USD ($)	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Fair Value, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Goodwill and Intangible Asset Impairment	$ 0	$ 0
Residential Mortgage-Backed Securities - Agency [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities, par value	$ 457,000,000
Available for sale securities, weighted average coupon rate (in percent)	4.10%
Available for sale securities, weighted average remaining maturity (in years)	4 years

Fair Value Measurements (Sche_2

Fair Value Measurements (Schedule of Financial Instruments Measured at Other Than Fair Value) (Details) - USD ($) $ in Millions		Mar. 31, 2024		Dec. 31, 2023
Estimated Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity investment securities		$ 238		$ 234
Net loan receivables		124,936		126,940
Cash and cash equivalents	[1]	14,004		11,685
Restricted cash	[1]	439		43
Accrued interest receivables	[1],[2]	1,490		1,450
Time deposits	[3]	45,276		45,333
Short-term debt, fair value				750
Long-term borrowings		20,372		20,304
Accrued interest payables	[1],[2]	445		421
Estimated Fair Value [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term borrowings		10,828		10,835
Estimated Fair Value [Member] | Consolidated Entity Excluding Variable Interest Entities (VIE) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term borrowings		9,544		9,469
Estimated Fair Value [Member] | Residential Mortgage-Backed Securities - Agency [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity investment securities		238		234
Estimated Fair Value [Member] | Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity investment securities		0		0
Net loan receivables		0		0
Cash and cash equivalents	[1]	14,004		11,685
Restricted cash	[1]	439		43
Accrued interest receivables	[1],[2]	0		0
Time deposits	[3]	0		0
Short-term debt, fair value				0
Long-term borrowings		0		0
Accrued interest payables	[1],[2]	0		0
Estimated Fair Value [Member] | Level 1 [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term borrowings		0		0
Estimated Fair Value [Member] | Level 1 [Member] | Consolidated Entity Excluding Variable Interest Entities (VIE) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term borrowings		0		0
Estimated Fair Value [Member] | Level 1 [Member] | Residential Mortgage-Backed Securities - Agency [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity investment securities		0		0
Estimated Fair Value [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity investment securities		238		234
Net loan receivables		0		0
Cash and cash equivalents	[1]	0		0
Restricted cash	[1]	0		0
Accrued interest receivables	[1],[2]	1,490		1,450
Time deposits	[3]	45,276		45,333
Short-term debt, fair value				750
Long-term borrowings		20,311		20,239
Accrued interest payables	[1],[2]	445		421
Estimated Fair Value [Member] | Level 2 [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term borrowings		10,767		10,770
Estimated Fair Value [Member] | Level 2 [Member] | Consolidated Entity Excluding Variable Interest Entities (VIE) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term borrowings		9,544		9,469
Estimated Fair Value [Member] | Level 2 [Member] | Residential Mortgage-Backed Securities - Agency [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity investment securities		238		234
Estimated Fair Value [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity investment securities		0		0
Net loan receivables		124,936		126,940
Cash and cash equivalents	[1]	0		0
Restricted cash	[1]	0		0
Accrued interest receivables	[1],[2]	0		0
Time deposits	[3]	0		0
Short-term debt, fair value				0
Long-term borrowings		61		65
Accrued interest payables	[1],[2]	0		0
Estimated Fair Value [Member] | Level 3 [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term borrowings		61		65
Estimated Fair Value [Member] | Level 3 [Member] | Consolidated Entity Excluding Variable Interest Entities (VIE) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term borrowings		0		0
Estimated Fair Value [Member] | Level 3 [Member] | Residential Mortgage-Backed Securities - Agency [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity investment securities		0		0
Carrying Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity investment securities		261		253
Net loan receivables		117,297		119,126
Cash and cash equivalents	[1]	14,004		11,685
Restricted cash	[1]	439		43
Accrued interest receivables	[1],[2]	1,490		1,450
Time deposits	[3]	45,242		45,240
Short-term debt, fair value				750
Long-term borrowings		20,475		20,581
Accrued interest payables	[1],[2]	445		421
Carrying Value [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term borrowings		10,933		10,993
Carrying Value [Member] | Consolidated Entity Excluding Variable Interest Entities (VIE) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term borrowings		9,542		9,588
Carrying Value [Member] | Residential Mortgage-Backed Securities - Agency [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity investment securities		261		253
Held-to-maturity investment securities	[4]	238		234
Residential Mortgage-Backed Securities - Agency [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity investment securities	[4],[5]	$ 238	[6]	$ 234
[1] The carrying values of these assets and liabilities approximate fair value due to their short-term nature. Accrued interest receivable and payable carrying values are presented as part of other assets and accrued expenses and other liabilities, respectively, in the Company's condensed consolidated statements of financial condition. Excludes deposits without contractually defined maturities for all periods presented. Held-to-maturity investment securities are reported at amortized cost. Amounts represent residential mortgage-backed securities ("RMBS") that were classified as held-to-maturity as they were entered into as a part of the Company's community reinvestment initiatives. Maturities of RMBS are reflective of the contractual maturities of the investment.

Derivatives and Hedging Activ_3

Derivatives and Hedging Activities (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Interest Income
Derivative [Line Items]
Cash flow hedge gain (loss) to be reclassified within twelve months	$ 104
Financing Receivable [Member]
Derivative [Line Items]
Initial maximum period for cash flow hedges (in years)	5 years	5 years

Derivatives and Hedging Activ_4

Derivatives and Hedging Activities (Schedule of Fair Value and Outstanding Notional Amounts of Derivative Instruments and Related Collateral Balances) (Details) € in Millions, £ in Millions, $ in Millions, $ in Millions, $ in Millions, ₨ in Billions		Mar. 31, 2024 USD ($) transactions	Mar. 31, 2024 EUR (€) transactions	Mar. 31, 2024 GBP (£) transactions	Mar. 31, 2024 SGD ($) transactions	Mar. 31, 2024 INR (₨) transactions	Dec. 31, 2023 USD ($) transactions		Dec. 31, 2023 EUR (€) transactions	Dec. 31, 2023 GBP (£) transactions	Dec. 31, 2023 SGD ($) transactions	Dec. 31, 2023 INR (₨) transactions	Dec. 31, 2023 AUD ($) transactions
Derivatives, Fair Value [Line Items]
Derivative assets	[1]	$ 1					$ 4	[2]
Derivative liabilities	[1]	11					0	[2]
Collateral held, derivative assets	[3]	0					0	[2]
Collateral posted, derivative liabilities	[3]	(11)					0	[2]
Total net derivative assets		1					4	[2]
Total net derivative liabilities		0					0	[2]
Designated as Hedges [Member] | Cash Flow Hedging [Member] | Interest Rate Swaps [Member]
Derivatives, Fair Value [Line Items]
Derivative, notional amount		$ 12,000					10,650
Derivative, number of outstanding derivative contracts | transactions		19	19	19	19	19
Derivative assets		$ 1					2	[2]
Derivative liabilities		6					0	[2]
Designated as Hedges [Member] | Fair Value Hedging [Member] | Interest Rate Swaps [Member]
Derivatives, Fair Value [Line Items]
Derivative, notional amount		$ 12,762					8,650
Derivative, number of outstanding derivative contracts | transactions		17	17	17	17	17
Derivative assets		$ 0					2	[2]
Derivative liabilities		5					0	[2]
Not Designated as Hedges [Member] | Foreign Exchange Forward [Member]
Derivatives, Fair Value [Line Items]
Derivative, notional amount	[4]	$ 32					29
Derivative, number of outstanding derivative contracts | transactions		6	6	6	6	6
Derivative assets		$ 0					0	[2]
Derivative liabilities		0					0	[2]
Not Designated as Hedges [Member] | Foreign Exchange Forward [Member] | Euro Member Countries, Euro
Derivatives, Fair Value [Line Items]
Derivative, notional amount | €			€ 6						€ 6
Not Designated as Hedges [Member] | Foreign Exchange Forward [Member] | United Kingdom, Pounds
Derivatives, Fair Value [Line Items]
Derivative, notional amount | £				£ 6						£ 6
Not Designated as Hedges [Member] | Foreign Exchange Forward [Member] | Singapore, Dollars
Derivatives, Fair Value [Line Items]
Derivative, notional amount					$ 1						$ 1
Not Designated as Hedges [Member] | Foreign Exchange Forward [Member] | India, Rupees
Derivatives, Fair Value [Line Items]
Derivative, notional amount | ₨						₨ 1.5						₨ 1.1
Not Designated as Hedges [Member] | Foreign Exchange Forward [Member] | Australia, Dollars
Derivatives, Fair Value [Line Items]
Derivative, notional amount													$ 2
Not Designated as Hedges [Member] | When-Issued Forward Contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative, notional amount		$ 23					$ 35
Derivative, number of outstanding derivative contracts | transactions		1	1	1	1	1	1		1	1	1	1	1
[1] In addition to the derivatives disclosed in the table, the Company enters into forward contracts to purchase when-issued mortgage-backed securities and tax exempt single family mortgage revenue bonds as part of its community reinvestment initiatives. At March 31, 2024, the Company had one outstanding contract with a total notional amount of $23 million and an immaterial fair value. At December 31, 2023, the Company had one outstanding contract with a total notional amount of $35 million and an immaterial fair value. Collateral amounts, which consist of cash and investment securities, are limited to the related derivative asset/liability balance and do not include excess collateral received/pledged.

Derivatives and Hedging Activ_5

Derivatives and Hedging Activities Derivatives and Hedging Activities (Schedule of Hedged Items in a Fair Value Hedging Relationship) (Details) - Long-term Debt [Member] - USD ($) $ in Millions		Mar. 31, 2024	Dec. 31, 2023
Schedule of Hedged Items in Fair Value Hedging Relationship [Line Items]
Carrying amount of hedged assets/liabilities		$ 12,614	$ 8,620
Hedged Liability, Fair Value Hedge, Cumulative Increase (Decrease)	[1]	(108)	0
Hedged Liability, Discontinued Fair Value Hedge, Cumulative Increase (Decrease)		$ 10	$ 12
[1] The balance includes $10 million and $12 million of cumulative hedging adjustments related to discontinued hedging relationships as of March 31, 2024 and December 31, 2023, respectively.

Derivatives and Hedging Activ_6

Derivatives and Hedging Activities (Schedule of Impact of the Derivative Instruments on Income) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Derivative Instruments, Gain (Loss) [Line Items]
Amounts reclassified from OCI into earnings, cash flow hedges	$ (37)	$ (5)
Interest Expense [Member] | Deposits [Member] | Designated as Hedges [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total amounts of income and expense line items presented in the condensed consolidated statements of income, where the effects of fair value or cash flow hedges are recorded	(1,210)	(756)
Interest Expense [Member] | Deposits [Member] | Designated as Hedges [Member] | Interest Rate Swaps [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amounts reclassified from OCI into earnings, cash flow hedges	0	0
Gains on hedged items, fair value hedges	3	0
Losses on interest rate swaps, fair value hedges	(4)	0
Total gains on fair value hedges	(1)	0
Interest Expense [Member] | Long-term Debt [Member] | Designated as Hedges [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total amounts of income and expense line items presented in the condensed consolidated statements of income, where the effects of fair value or cash flow hedges are recorded	(245)	(189)
Interest Expense [Member] | Long-term Debt [Member] | Designated as Hedges [Member] | Interest Rate Swaps [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amounts reclassified from OCI into earnings, cash flow hedges	3	2
Gains on hedged items, fair value hedges	103	(35)
Losses on interest rate swaps, fair value hedges	(138)	21
Total gains on fair value hedges	(35)	(14)
Interest Income | Credit Card Loans [Member] | Designated as Hedges [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total amounts of income and expense line items presented in the condensed consolidated statements of income, where the effects of fair value or cash flow hedges are recorded	3,938	3,321
Interest Income | Credit Card Loans [Member] | Designated as Hedges [Member] | Interest Rate Swaps [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amounts reclassified from OCI into earnings, cash flow hedges	(40)	(7)
Gains on hedged items, fair value hedges	0	0
Losses on interest rate swaps, fair value hedges	0	0
Total gains on fair value hedges	$ 0	$ 0

Segment Disclosures (Narrative)

Segment Disclosures (Narrative) (Details)	3 Months Ended
	Mar. 31, 2024 segment
Segment Reporting [Abstract]
Number of reportable segments (in number of segments)	2

Segment Disclosures (Schedule o

Segment Disclosures (Schedule of Segment Disclosures) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Segment Reporting Information [Line Items]
Interest income	$ 4,948	$ 4,077
Interest expense	1,461	945
Net interest income	3,487	3,132
Provision for credit losses	1,497	1,102
Other income	723	610
Other expense	2,309	1,383
Income before income taxes	404	1,257
Credit Card Loans [Member]
Segment Reporting Information [Line Items]
Interest income	3,938	3,321
Total Other Loans [Member] | Private Student Loans [Member]
Segment Reporting Information [Line Items]
Interest income	264	252
Total Other Loans [Member] | Personal Loans [Member]
Segment Reporting Information [Line Items]
Interest income	333	248
Total Other Loans [Member] | Other Loans [Member]
Segment Reporting Information [Line Items]
Interest income	115	64
Unallocated Financing Receivables | Other [Member]
Segment Reporting Information [Line Items]
Interest income	298	192
Operating Segments [Member] | Digital Banking [Member]
Segment Reporting Information [Line Items]
Interest income	4,948	4,077
Interest expense	1,461	945
Net interest income	3,487	3,132
Provision for credit losses	1,497	1,102
Other income	591	522
Other expense	2,259	1,342
Income before income taxes	322	1,210
Operating Segments [Member] | Digital Banking [Member] | Credit Card Loans [Member]
Segment Reporting Information [Line Items]
Interest income	3,938	3,321
Operating Segments [Member] | Digital Banking [Member] | Total Other Loans [Member] | Private Student Loans [Member]
Segment Reporting Information [Line Items]
Interest income	264	252
Operating Segments [Member] | Digital Banking [Member] | Total Other Loans [Member] | Personal Loans [Member]
Segment Reporting Information [Line Items]
Interest income	333	248
Operating Segments [Member] | Digital Banking [Member] | Total Other Loans [Member] | Other Loans [Member]
Segment Reporting Information [Line Items]
Interest income	115	64
Operating Segments [Member] | Digital Banking [Member] | Unallocated Financing Receivables | Other [Member]
Segment Reporting Information [Line Items]
Interest income	298	192
Operating Segments [Member] | Payment Services [Member]
Segment Reporting Information [Line Items]
Interest income	0	0
Interest expense	0	0
Net interest income	0	0
Provision for credit losses	0	0
Other income	132	88
Other expense	50	41
Income before income taxes	82	47
Operating Segments [Member] | Payment Services [Member] | Credit Card Loans [Member]
Segment Reporting Information [Line Items]
Interest income	0	0
Operating Segments [Member] | Payment Services [Member] | Total Other Loans [Member] | Private Student Loans [Member]
Segment Reporting Information [Line Items]
Interest income	0	0
Operating Segments [Member] | Payment Services [Member] | Total Other Loans [Member] | Personal Loans [Member]
Segment Reporting Information [Line Items]
Interest income	0	0
Operating Segments [Member] | Payment Services [Member] | Total Other Loans [Member] | Other Loans [Member]
Segment Reporting Information [Line Items]
Interest income	0	0
Operating Segments [Member] | Payment Services [Member] | Unallocated Financing Receivables | Other [Member]
Segment Reporting Information [Line Items]
Interest income	$ 0	$ 0

Revenue from Contracts with C_3

Revenue from Contracts with Customers (Schedule of Revenue from Contracts with Customers Disaggregated by Business Segment) (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2024	Mar. 31, 2023
Disaggregation of Revenue [Line Items]
Discount and interchange revenue, net		$ 371	$ 330
Protection products revenue		42	43
Transaction processing revenue		87	67
Other income		23	22
Loan fee income		200	166
Gains (losses) on equity investments		0	(18)
Total other income		723	610
Customer rewards included in discount and interchange revenue		703	716
Deposit product fees reported in net interest income and excluded from other income subject to ASC 606		2	6
Noninterest Income not Subject to ASC 606		200	148
Accounting Standards Update 2014-09 [Member]
Disaggregation of Revenue [Line Items]
Discount and interchange revenue, net	[1]	371	330
Protection products revenue		42	43
Transaction processing revenue		87	67
Other income		23	22
Total other income subject to ASC 606	[2]	523	462
Operating Segments [Member] | Digital Banking [Member]
Disaggregation of Revenue [Line Items]
Loan fee income		200	166
Gains (losses) on equity investments			0
Total other income		591	522
Noninterest Income not Subject to ASC 606		200	166
Operating Segments [Member] | Digital Banking [Member] | Accounting Standards Update 2014-09 [Member]
Disaggregation of Revenue [Line Items]
Discount and interchange revenue, net	[1]	346	310
Protection products revenue		42	43
Transaction processing revenue		0	0
Other income		3	3
Total other income subject to ASC 606	[2]	391	356
Operating Segments [Member] | Payment Services [Member]
Disaggregation of Revenue [Line Items]
Loan fee income		0	0
Gains (losses) on equity investments			(18)
Total other income		132	88
Noninterest Income not Subject to ASC 606		0	(18)
Operating Segments [Member] | Payment Services [Member] | Accounting Standards Update 2014-09 [Member]
Disaggregation of Revenue [Line Items]
Discount and interchange revenue, net	[1]	25	20
Protection products revenue		0	0
Transaction processing revenue		87	67
Other income		20	19
Total other income subject to ASC 606	[2]	$ 132	$ 106
[1] Net of rewards, including Cashback Bonus rewards, of $703 million and $716 million for the three months ended March 31, 2024 and 2023, respectively. Excludes $2 million and $6 million of deposit product fees that are reported within net interest income for the three months ended March 31, 2024 and 2023, respectively.