Investments (Details) - Table - HTM Securities (Amortized Cost & Fair Values) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
HTM Securities
Amortized Cost	$ 681	$ 903
Gross Unrecognized Holding Gains	1	2
Gross Unrecognized Holding Losses	(12)	(13)
Estimated Fair Value	670	892
MBS - Other U.S. Obligations
HTM Securities
Amortized Cost	16	18
Gross Unrecognized Holding Gains	0	0
Gross Unrecognized Holding Losses	0	0
Estimated Fair Value	16	18
PLRMBS
HTM Securities
Amortized Cost	77	80
Gross Unrecognized Holding Gains	0	0
Gross Unrecognized Holding Losses	(4)	(4)
Estimated Fair Value	73	76
MBS - GSEs
HTM Securities
Amortized Cost	588	805
Gross Unrecognized Holding Gains	1	2
Gross Unrecognized Holding Losses	(8)	(9)
Estimated Fair Value	581	798
Single-family \| MBS - GSEs
HTM Securities
Amortized Cost	382	401
Gross Unrecognized Holding Gains	1	2
Gross Unrecognized Holding Losses	(8)	(8)
Estimated Fair Value	375	395
Multifamily \| MBS - GSEs
HTM Securities
Amortized Cost	206	404
Gross Unrecognized Holding Gains	0	0
Gross Unrecognized Holding Losses	0	(1)
Estimated Fair Value	$ 206	$ 403

Amount excluding accrued interest, after allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity).

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