Investment Securities - Schedule of Investment Securities (Details) - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025
Debt securities available-for-sale
Fair Value	$ 16,553	$ 15,701
Amortized cost of investment securities	2	2
Interest receivable	$ 63	$ 58
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration]	Other assets	Other assets
Asset Pledged as Collateral
Debt securities available-for-sale
Investment securities pledged	$ 16,300	$ 15,400
Mortgage Backed Securities And Other Securities
Debt securities available-for-sale
Amortized Cost	17,289	16,310
Gross Unrealized Gain	45	91
Gross Unrealized Loss	781	700
Fair Value	16,553	15,701
Mortgage- Related Securities
Debt securities available-for-sale
Amortized Cost	14,385	13,392
Gross Unrealized Gain	38	69
Gross Unrealized Loss	548	479
Fair Value	13,875	12,982
GSE CMOs
Debt securities available-for-sale
Amortized Cost	13,168	12,129
Gross Unrealized Gain	27	55
Gross Unrealized Loss	423	360
Fair Value	12,772	11,824
GSE certificates
Debt securities available-for-sale
Amortized Cost	1,075	1,116
Gross Unrealized Gain	1	2
Gross Unrealized Loss	125	119
Fair Value	951	999
Private label CMOs
Debt securities available-for-sale
Amortized Cost	142	147
Gross Unrealized Gain	10	12
Gross Unrealized Loss	0	0
Fair Value	152	159
Debt Securities
Debt securities available-for-sale
Amortized Cost	2,904	2,918
Gross Unrealized Gain	7	22
Gross Unrealized Loss	233	221
Fair Value	2,678	2,719
GSE debentures
Debt securities available-for-sale
Amortized Cost	1,501	1,502
Gross Unrealized Gain	0	0
Gross Unrealized Loss	218	206
Fair Value	1,283	1,296
U. S. Treasury obligations
Debt securities available-for-sale
Amortized Cost	1,000	1,001
Gross Unrealized Gain	1	16
Gross Unrealized Loss	2	0
Fair Value	999	1,017
Asset-backed securities
Debt securities available-for-sale
Amortized Cost	203	217
Gross Unrealized Gain	0	0
Gross Unrealized Loss	4	4
Fair Value	199	213
Corporate bonds
Debt securities available-for-sale
Amortized Cost	148	147
Gross Unrealized Gain	0	0
Gross Unrealized Loss	2	3
Fair Value	146	144
Capital trust notes
Debt securities available-for-sale
Amortized Cost	48	47
Gross Unrealized Gain	6	6
Gross Unrealized Loss	7	8
Fair Value	47	45
Municipal bonds
Debt securities available-for-sale
Amortized Cost	4	4
Gross Unrealized Gain	0	0
Gross Unrealized Loss	0	0
Fair Value	$ 4	$ 4

Debt Securities, Available For Sale, Excluding Interest And Equity Securities, Current

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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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