Investment Securities - Contractual Maturities and Weighted-Average Yields of Securities (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2025	Dec. 31, 2024
Fair value of securities available for sale:
Due in 1 Year or Less	$ 4,035
Due > 1 Year through 5 Years	9,034
Due > 5 Years through 10 Years	6,563
Due > 10 Years	67,564
Total	87,196	$ 83,013
Amortized cost of securities available for sale
Due in 1 Year or Less	4,039
Due > 1 Year through 5 Years	9,121
Due > 5 Years through 10 Years	6,778
Due > 10 Years	75,486
Total	$ 95,424	92,995
Weighted-average yield for securities available for sale
Due in 1 Year or Less	4.19%
Due > 1 Year through 5 Years	3.93%
Due > 5 Years through 10 Years	3.99%
Due > 10 Years	3.82%
Total	3.86%
U.S. Treasury securities
Fair value of securities available for sale:
Due in 1 Year or Less	$ 2,718
Due > 1 Year through 5 Years	2,706
Due > 5 Years through 10 Years	2,985
Due > 10 Years	0
Total	8,409	6,110
Amortized cost of securities available for sale
Total	8,397	6,114
RMBS, Agency
Fair value of securities available for sale:
Due in 1 Year or Less	2
Due > 1 Year through 5 Years	106
Due > 5 Years through 10 Years	1,191
Due > 10 Years	65,025
Total	66,324	64,707
Amortized cost of securities available for sale
Total	74,225	74,177
RMBS, Non-agency
Fair value of securities available for sale:
Due in 1 Year or Less	0
Due > 1 Year through 5 Years	0
Due > 5 Years through 10 Years	27
Due > 10 Years	586
Total	613	621
Amortized cost of securities available for sale
Total	547	567
Total RMBS
Fair value of securities available for sale:
Due in 1 Year or Less	2
Due > 1 Year through 5 Years	106
Due > 5 Years through 10 Years	1,218
Due > 10 Years	65,611
Total	66,937	65,328
Amortized cost of securities available for sale
Total	$ 74,772	74,744
Weighted-average yield for securities available for sale
Weighted-average expected life	7 years 10 months 24 days
Agency CMBS
Fair value of securities available for sale:
Due in 1 Year or Less	$ 1,143
Due > 1 Year through 5 Years	3,022
Due > 5 Years through 10 Years	2,360
Due > 10 Years	1,915
Total	8,440	7,825
Amortized cost of securities available for sale
Total	$ 8,848	8,389
Weighted-average yield for securities available for sale
Weighted-average expected life	4 years 4 months 24 days
Other securities
Fair value of securities available for sale:
Due in 1 Year or Less	$ 172
Due > 1 Year through 5 Years	3,200
Due > 5 Years through 10 Years	0
Due > 10 Years	38
Total	3,410	3,750
Amortized cost of securities available for sale
Total	$ 3,407	$ 3,748

Available-for-sale Securities, Expected Debt Maturities, Amortized Cost Basis, Rolling Maturity

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