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Business Segments and Revenue from Contracts with Customers - Segment Results and Reconciliation (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Segment Reporting Information [Line Items] |  |  |
Net interest income (loss) | $ 29,241 | $ 27,114 | $ 24,171
Non-interest income (loss) | 7,546 | 7,136 | 6,264
Total net revenue (loss) | 36,787 | 34,250 | 30,435
Provision for credit losses | 10,426 | 5,847 | (1,944)
Non-interest expense | 20,316 | 19,163 | 16,570
Income (loss) from continuing operations before income taxes | 6,045 | 9,240 | 15,809
Income tax provision (benefit) | 1,158 | 1,880 | 3,415
Income (loss) from continuing operations, net of tax | 4,887 | 7,360 | 12,394
Total loans held for investment |  | 312,331 | 277,340
Deposits | 348,413 | 332,992 | 310,980
Uncollectible portion of billed finance charges and fees | 1,900 | 946 | 629
Operating segments | Credit Card |  |  |
Segment Reporting Information [Line Items] |  |  |
Net interest income (loss) | 19,729 | 16,584 | 14,074
Non-interest income (loss) | 5,940 | 5,771 | 4,806
Total net revenue (loss) | 25,669 | 22,355 | 18,880
Provision for credit losses | 8,651 | 4,265 | (902)
Non-interest expense | 12,490 | 11,627 | 9,621
Income (loss) from continuing operations before income taxes | 4,528 | 6,463 | 10,161
Income tax provision (benefit) | 1,071 | 1,536 | 2,403
Income (loss) from continuing operations, net of tax | 3,457 | 4,927 | 7,758
Total loans held for investment | 154,547 | 137,730 | 114,772
Deposits | 0 | 0 | 0
Operating segments | Consumer Banking |  |  |
Segment Reporting Information [Line Items] |  |  |
Net interest income (loss) | 8,713 | 8,965 | 8,448
Non-interest income (loss) | 589 | 469 | 554
Total net revenue (loss) | 9,302 | 9,434 | 9,002
Provision for credit losses | 1,169 | 1,173 | (521)
Non-interest expense | 5,178 | 5,312 | 4,711
Income (loss) from continuing operations before income taxes | 2,955 | 2,949 | 4,812
Income tax provision (benefit) | 697 | 699 | 1,136
Income (loss) from continuing operations, net of tax | 2,258 | 2,250 | 3,676
Total loans held for investment | 75,437 | 79,925 | 77,646
Deposits | 296,171 | 270,592 | 256,407
Operating segments | Commercial Banking |  |  |
Segment Reporting Information [Line Items] |  |  |
Net interest income (loss) | 2,518 | 2,461 | 2,153
Non-interest income (loss) | 1,002 | 1,129 | 1,148
Total net revenue (loss) | 3,520 | 3,590 | 3,301
Provision for credit losses | 605 | 415 | (519)
Non-interest expense | 2,011 | 2,070 | 1,815
Income (loss) from continuing operations before income taxes | 904 | 1,105 | 2,005
Income tax provision (benefit) | 213 | 262 | 473
Income (loss) from continuing operations, net of tax | 691 | 843 | 1,532
Total loans held for investment | 90,488 | 94,676 | 84,922
Deposits | 32,712 | 40,808 | 44,809
Other |  |  |
Segment Reporting Information [Line Items] |  |  |
Net interest income (loss) | (1,719) | (896) | (504)
Non-interest income (loss) | 15 | (233) | (244)
Total net revenue (loss) | (1,704) | (1,129) | (748)
Provision for credit losses | 1 | (6) | (2)
Non-interest expense | 637 | 154 | 423
Income (loss) from continuing operations before income taxes | (2,342) | (1,277) | (1,169)
Income tax provision (benefit) | (823) | (617) | (597)
Income (loss) from continuing operations, net of tax | (1,519) | (660) | (572)
Total loans held for investment | 0 | 0 | 0
Deposits | $ 19,530 | $ 21,592 | $ 9,764

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