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Securities - Details of Securities (Details) - USD ($) $ in Millions | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | ---
SECURITIES AVAILABLE FOR SALE |  |
Total | $ 42,695 | $ 45,552
Gross Unrealized Gains | 10 | 2
Gross Unrealized Losses | 5,520 | 6,437
Securities available for sale | 37,185 | 39,117
HELD-TO-MATURITY SECURITIES |  |
Total | 8,575 | 8,710
Gross Unrealized Gains | 10 | 6
Gross Unrealized Losses | 529 | 603
Fair Value | $ 8,056 | $ 8,113
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration] | Accrued income and other assets | Accrued income and other assets
Debt Securities, Held-to-Maturity, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration] | Accrued income and other assets | Accrued income and other assets
Available-for-sale securities, accrued interest | $ 64 | $ 67
Held-to-maturity securities, accrued interest | 25 | 88
U.S. Treasury, agencies, and corporations |  |
SECURITIES AVAILABLE FOR SALE |  |
Total | 9,300 | 10,044
Gross Unrealized Gains | 6 | 0
Gross Unrealized Losses | 280 | 629
Securities available for sale | 9,026 | 9,415
Agency residential collateralized mortgage obligations |  |
SECURITIES AVAILABLE FOR SALE |  |
Total | 18,911 | 20,180
Gross Unrealized Gains | 4 | 0
Gross Unrealized Losses | 3,437 | 3,747
Securities available for sale | 15,478 | 16,433
HELD-TO-MATURITY SECURITIES |  |
Total | 5,170 | 4,586
Gross Unrealized Gains | 9 | 5
Gross Unrealized Losses | 283 | 283
Fair Value | 4,896 | 4,308
Agency residential mortgage-backed securities |  |
SECURITIES AVAILABLE FOR SALE |  |
Total | 4,189 | 4,616
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 600 | 696
Securities available for sale | 3,589 | 3,920
HELD-TO-MATURITY SECURITIES |  |
Total | 165 | 181
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 13 | 16
Fair Value | 152 | 165
Agency commercial mortgage-backed securities |  |
SECURITIES AVAILABLE FOR SALE |  |
Total | 10,295 | 10,712
Gross Unrealized Gains | 0 | 2
Gross Unrealized Losses | 1,203 | 1,365
Securities available for sale | 9,092 | 9,349
HELD-TO-MATURITY SECURITIES |  |
Total | 2,473 | 2,522
Gross Unrealized Gains | 1 | 1
Gross Unrealized Losses | 204 | 208
Fair Value | 2,270 | 2,315
Asset-backed securities |  |
HELD-TO-MATURITY SECURITIES |  |
Total | 738 | 1,407
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 29 | 96
Fair Value | 709 | 1,311
Securities related to purchase of senior notes | 731 | 1,400
Other securities |  |
SECURITIES AVAILABLE FOR SALE |  |
Total | 0 | 0
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 0 | 0
Securities available for sale | 0 | 0
HELD-TO-MATURITY SECURITIES |  |
Total | 29 | 14
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 0 | 0
Fair Value | $ 29 | $ 14

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