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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, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Segment Reporting Information [Line Items] |  |  |
Net interest income (loss) | $ 24,171 | $ 22,913 | $ 23,340
Non-interest income (loss) | 6,264 | 5,610 | 5,253
Total net revenue (loss) | 30,435 | 28,523 | 28,593
Provision (benefit) for credit losses | (1,944) | 10,264 | 6,236
Non-interest expense | 16,570 | 15,056 | 15,483
Income (loss) from continuing operations before income taxes | 15,809 | 3,203 | 6,874
Income tax provision | 3,415 | 486 | 1,341
Income (loss) from continuing operations, net of tax | 12,394 | 2,717 | 5,533
Total loans held for investment | 277,340 | 251,624 | 265,809
Total Deposits | 310,980 | 305,442 | 262,697
Uncollectible portion of billed finance charges and fees | 629 | 1,100 | 1,400
Operating segments | Credit Card |  |  |
Segment Reporting Information [Line Items] |  |  |
Net interest income (loss) | 14,074 | 13,776 | 14,461
Non-interest income (loss) | 4,806 | 3,823 | 3,888
Total net revenue (loss) | 18,880 | 17,599 | 18,349
Provision (benefit) for credit losses | (902) | 7,327 | 4,992
Non-interest expense | 9,621 | 8,491 | 9,271
Income (loss) from continuing operations before income taxes | 10,161 | 1,781 | 4,086
Income tax provision | 2,403 | 420 | 959
Income (loss) from continuing operations, net of tax | 7,758 | 1,361 | 3,127
Total loans held for investment | 114,772 | 106,956 | 128,236
Total Deposits | 0 | 0 | 0
Operating segments | Consumer Banking |  |  |
Segment Reporting Information [Line Items] |  |  |
Net interest income (loss) | 8,448 | 7,238 | 6,732
Non-interest income (loss) | 554 | 466 | 643
Total net revenue (loss) | 9,002 | 7,704 | 7,375
Provision (benefit) for credit losses | (521) | 1,753 | 938
Non-interest expense | 4,711 | 4,159 | 4,091
Income (loss) from continuing operations before income taxes | 4,812 | 1,792 | 2,346
Income tax provision | 1,136 | 425 | 547
Income (loss) from continuing operations, net of tax | 3,676 | 1,367 | 1,799
Total loans held for investment | 77,646 | 68,888 | 63,065
Total Deposits | 256,407 | 249,815 | 213,099
Operating segments | Commercial Banking |  |  |
Segment Reporting Information [Line Items] |  |  |
Net interest income (loss) | 2,153 | 2,048 | 1,983
Non-interest income (loss) | 1,148 | 923 | 831
Total net revenue (loss) | 3,301 | 2,971 | 2,814
Provision (benefit) for credit losses | (519) | 1,181 | 306
Non-interest expense | 1,815 | 1,706 | 1,699
Income (loss) from continuing operations before income taxes | 2,005 | 84 | 809
Income tax provision | 473 | 19 | 188
Income (loss) from continuing operations, net of tax | 1,532 | 65 | 621
Total loans held for investment | 84,922 | 75,780 | 74,508
Total Deposits | 44,809 | 39,590 | 32,134
Other |  |  |
Segment Reporting Information [Line Items] |  |  |
Net interest income (loss) | (504) | (149) | 164
Non-interest income (loss) | (244) | 398 | (109)
Total net revenue (loss) | (748) | 249 | 55
Provision (benefit) for credit losses | (2) | 3 | 0
Non-interest expense | 423 | 700 | 422
Income (loss) from continuing operations before income taxes | (1,169) | (454) | (367)
Income tax provision | (597) | (378) | (353)
Income (loss) from continuing operations, net of tax | (572) | (76) | (14)
Total loans held for investment | 0 | 0 | 0
Total Deposits | $ 9,764 | $ 16,037 | $ 17,464

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