Investment Securities - Contractual Maturities and Weighted-Average Yields of Securities (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
Fair value of securities available for sale:
Due in 1 Year or Less	$ 4,274
Due > 1 Year through 5 Years	7,990
Due > 5 Years through 10 Years	8,476
Due > 10 Years	70,311
Total	91,051	$ 83,013
Amortized cost basis of securities available for sale
Due in 1 Year or Less	4,276
Due > 1 Year through 5 Years	8,030
Due > 5 Years through 10 Years	8,622
Due > 10 Years	76,728
Total	$ 97,656	92,995
Weighted-average yield for securities available for sale
Due in 1 Year or Less	4.05%
Due > 1 Year through 5 Years	3.89%
Due > 5 Years through 10 Years	3.98%
Due > 10 Years	3.39%
Total	3.51%
U.S. Treasury securities
Fair value of securities available for sale:
Due in 1 Year or Less	$ 3,304
Due > 1 Year through 5 Years	1,810
Due > 5 Years through 10 Years	4,899
Due > 10 Years	0
Total	10,013	6,110
Amortized cost basis of securities available for sale
Total	9,958	6,114
RMBS, Agency
Fair value of securities available for sale:
Due in 1 Year or Less	3
Due > 1 Year through 5 Years	148
Due > 5 Years through 10 Years	1,070
Due > 10 Years	67,920
Total	69,141	64,707
Amortized cost basis of securities available for sale
Total	75,561	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	36
Due > 10 Years	551
Total	587	621
Amortized cost basis of securities available for sale
Total	525	567
Total RMBS
Fair value of securities available for sale:
Due in 1 Year or Less	3
Due > 1 Year through 5 Years	148
Due > 5 Years through 10 Years	1,106
Due > 10 Years	68,471
Total	69,728	65,328
Amortized cost basis of securities available for sale
Total	$ 76,086	74,744
Weighted-average yield for securities available for sale
Weighted-average expected life	7 years 7 months 6 days
Agency CMBS
Fair value of securities available for sale:
Due in 1 Year or Less	$ 778
Due > 1 Year through 5 Years	2,896
Due > 5 Years through 10 Years	2,471
Due > 10 Years	1,747
Total	7,892	7,825
Amortized cost basis of securities available for sale
Total	$ 8,201	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	$ 189
Due > 1 Year through 5 Years	3,136
Due > 5 Years through 10 Years	0
Due > 10 Years	93
Total	3,418	3,750
Amortized cost basis of securities available for sale
Total	$ 3,411	$ 3,748

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

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