Investments (Details) - Table - HTM Securities (Amortized Cost & Fair Values) - USD ($) $ in Millions	Sep. 30, 2026	Dec. 31, 2025
HTM Securities
HTM Securities	$ 584	$ 903
Gross Unrecognized Holding Gains	2	2
Gross Unrecognized Holding Losses	(15)	(13)
Estimated Fair Value	571	892
MBS - Other U.S. Obligations
HTM Securities
HTM Securities	12	18
Gross Unrecognized Holding Gains	0	0
Gross Unrecognized Holding Losses	0	0
Estimated Fair Value	12	18
PLRMBS
HTM Securities
HTM Securities	68	80
Gross Unrecognized Holding Gains	0	0
Gross Unrecognized Holding Losses	(5)	(4)
Estimated Fair Value	63	76
MBS - GSEs
HTM Securities
HTM Securities	504	805
Gross Unrecognized Holding Gains	2	2
Gross Unrecognized Holding Losses	(10)	(9)
Estimated Fair Value	496	798
Single-family \| MBS - GSEs
HTM Securities
HTM Securities	344	401
Gross Unrecognized Holding Gains	2	2
Gross Unrecognized Holding Losses	(10)	(8)
Estimated Fair Value	336	395
Multifamily \| MBS - GSEs
HTM Securities
HTM Securities	160	404
Gross Unrecognized Holding Gains	0	0
Gross Unrecognized Holding Losses	0	(1)
Estimated Fair Value	$ 160	$ 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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