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- Definition

Notional Amount Of Derivatives Not Designated As Hedging Instruments Additions During The Period

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- Definition

Notional Amount Of Derivatives Not Designated As Hedging Instruments Settlement Expiration During The Period

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- Definition

Notional Amount Of Trading Securities Settlement Expiration During The Period

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Trading Securities Added During the Period

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- Definition

Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

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Nominal or face amount used to calculate payments on the derivative liability.

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Nominal or face amount used to calculate payment on derivative.

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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Derivative and Other Hedging Instruments (Effect Of Derivative Instruments Not Designated As Hedges On Comprehensive Income Statement) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024	Dec. 31, 2023
Changes in Derivative and Other Hedge Portfolio [Roll Forward]
Amount Gain/(Loss) Recognized in Income on Derivatives	$ (1,011)	$ 1,102
Interest Rate Swaption [Member]
Changes in Derivative and Other Hedge Portfolio [Roll Forward]
Notional Amount	(2,000)	0	$ (2,000)
Additions	(1,500)	0
Settlement, Expirations or Exercise	1,500	1,250
Amount Gain/(Loss) Recognized in Income on Derivatives	(19)	33
TBA and Forward Settling Agency Securities [Member]
Changes in Derivative and Other Hedge Portfolio [Roll Forward]
Notional Amount	(7,811)	(8,651)	(6,955)	$ (5,332)
Additions	(27,967)	(25,390)
Settlement, Expirations or Exercise		22,071
Amount Gain/(Loss) Recognized in Income on Derivatives	77	(58)
Purchases Of TBAs And Forward Settling Agency Securities [Member]
Changes in Derivative and Other Hedge Portfolio [Roll Forward]
Settlement, Expirations or Exercise	27,111
Interest Rate Swap [Member]
Changes in Derivative and Other Hedge Portfolio [Roll Forward]
Additions	(8,150)	(5,170)
Settlement, Expirations or Exercise	0	5,250
Notional Amount	(47,796)
Amount Gain/(Loss) Recognized in Income on Derivatives	(569)	658
US Treasury Securities [Member]
Changes in Derivative and Other Hedge Portfolio [Roll Forward]
Amount Gain/(Loss) Recognized in Income on Derivatives	(100)	186
Receiver Swaption [Member]
Changes in Derivative and Other Hedge Portfolio [Roll Forward]
Notional Amount	(150)	(150)	(150)	(150)
Additions	0	0
Settlement, Expirations or Exercise	0	0
Amount Gain/(Loss) Recognized in Income on Derivatives	0	0
Credit Default Swap, Buying Protection
Changes in Derivative and Other Hedge Portfolio [Roll Forward]
Additions		0
Settlement, Expirations or Exercise		0
Amount Gain/(Loss) Recognized in Income on Derivatives		(3)
SOFR Futures Contracts
Changes in Derivative and Other Hedge Portfolio [Roll Forward]
Notional Amount	(1,200)		(1,200)
Interest Rate Receive Swap
Changes in Derivative and Other Hedge Portfolio [Roll Forward]
Additions		0
Settlement, Expirations or Exercise		0
Amount Gain/(Loss) Recognized in Income on Derivatives		(9)
Not Designated as Hedging Instrument [Member] \| Interest Rate Swaption [Member]
Changes in Derivative and Other Hedge Portfolio [Roll Forward]
Notional Amount				(1,250)
Not Designated as Hedging Instrument [Member] \| Interest Rate Swap [Member]
Changes in Derivative and Other Hedge Portfolio [Roll Forward]
Notional Amount	(47,796)	(44,396)	(39,646)	(44,476)
Not Designated as Hedging Instrument [Member] \| Credit Default Swap, Buying Protection
Changes in Derivative and Other Hedge Portfolio [Roll Forward]
Notional Amount		(96)		(96)
Not Designated as Hedging Instrument [Member] \| Interest Rate Receive Swap
Changes in Derivative and Other Hedge Portfolio [Roll Forward]
Notional Amount		(1,000)		(1,000)
Short [Member] \| US Treasury Securities [Member]
Changes in Derivative and Other Hedge Portfolio [Roll Forward]
Notional Amount	(17,636)	(12,807)	(17,792)	(11,347)
Additions	(3,821)	(3,101)
Settlement, Expirations or Exercise	3,977	1,641
Amount Gain/(Loss) Recognized in Income on Derivatives	(460)	338
Long [Member] \| US Treasury Securities [Member]
Changes in Derivative and Other Hedge Portfolio [Roll Forward]
Amount Gain/(Loss) Recognized in Income on Derivatives	60	(43)
Debt Securities, Trading, and Equity Securities, FV-NI	3,216	1,815	1,585	1,492
Trading Securities Added During the Period	5,388	1,669
Notional Amount Of Trading Securities Settlement Expiration During The Period	(3,757)	(1,346)
Long [Member] \| SOFR Futures Contracts
Changes in Derivative and Other Hedge Portfolio [Roll Forward]
Amount Gain/(Loss) Recognized in Income on Derivatives	10	(10)
Future [Member] \| Short [Member] \| US Treasury Securities [Member]
Changes in Derivative and Other Hedge Portfolio [Roll Forward]
Notional Amount	(1,523)	(3,039)	$ (4,373)	$ (6,429)
Additions	1,441	(3,384)
Settlement, Expirations or Exercise	$ (4,291)	$ 6,774