Investment Securities - Carrying Amounts and Fair Values of Investment Securities (Detail) - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025
Held-to-maturity
Amortized cost	$ 1,676	$ 1,584
Gross unrealized gains	2	3
Gross unrealized (losses)	(181)	(160)
Investment securities - HTM, fair value	1,497	1,427
Available-for-sale debt securities
Amortized Cost	19,547	19,303
Gross unrealized gains	19	95
Gross unrealized (losses)	(686)	(610)
Fair value	18,880	18,788
CLO
Available-for-sale debt securities
Amortized Cost	3,218	2,743
Gross unrealized gains	5	4
Gross unrealized (losses)	(2)	0
Fair value	3,221	2,747
Commercial MBS issued by GSEs and GNMA
Available-for-sale debt securities
Amortized Cost	523	638
Gross unrealized gains	1	5
Gross unrealized (losses)	(10)	(8)
Fair value	514	635
Corporate debt securities
Available-for-sale debt securities
Amortized Cost	229	308
Gross unrealized gains	0	0
Gross unrealized (losses)	(7)	(11)
Fair value	222	297
Private label residential MBS
Held-to-maturity
Amortized cost	159	165
Gross unrealized gains	0	0
Gross unrealized (losses)	(29)	(28)
Investment securities - HTM, fair value	130	137
Available-for-sale debt securities
Amortized Cost	1,289	1,185
Gross unrealized gains	0	2
Gross unrealized (losses)	(153)	(148)
Fair value	1,136	1,039
Residential MBS issued by GSEs and GNMA
Available-for-sale debt securities
Amortized Cost	7,767	7,489
Gross unrealized gains	13	52
Gross unrealized (losses)	(352)	(311)
Fair value	7,428	7,230
Tax-exempt
Held-to-maturity
Amortized cost	1,517	1,419
Gross unrealized gains	2	3
Gross unrealized (losses)	(152)	(132)
Investment securities - HTM, fair value	1,367	1,290
Available-for-sale debt securities
Amortized Cost	860	879
Gross unrealized gains	0	0
Gross unrealized (losses)	(66)	(77)
Fair value	794	802
U.S. Treasury securities
Available-for-sale debt securities
Amortized Cost	5,583	5,986
Gross unrealized gains	0	31
Gross unrealized (losses)	(89)	(47)
Fair value	5,494	5,970
Other
Available-for-sale debt securities
Amortized Cost	78	75
Gross unrealized gains	0	1
Gross unrealized (losses)	(7)	(8)
Fair value	$ 71	$ 68

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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