Derivative Instruments - Schedule of Notional and Fair Value Position (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Derivative [Line Items]
Notional amount	$ 364,927	$ 366,384
Asset Derivatives
Netting adjustment	(154)	(237)
Derivative assets	175	171
Liability Derivatives
Derivatives liabilities at fair value	(168)	(233)
Table Footnote
Cash collateral posted for derivative instruments	4,500	966
Cash collateral received for derivative instruments	$ 5	$ 30
Derivative Asset, Statement of Financial Position [Extensible Enumeration]	Other assets	Other assets
Derivative Liability, Statement of Financial Position [Extensible Enumeration]	Other liabilities	Other liabilities
Total risk management derivatives portfolio
Derivative [Line Items]
Notional amount	$ 285,437	$ 164,742
Asset Derivatives
Netting adjustment	(154)	(237)
Derivative assets	83	2
Liability Derivatives
Netting adjustment	4,662	1,173
Derivatives liabilities at fair value	(24)	(15)
Total risk management derivatives portfolio | Designated as Hedging Instrument
Asset Derivatives
Derivative assets, gross	0	0
Liability Derivatives
Derivative liabilities, gross	0	0
Total risk management derivatives portfolio | Not Designated as Hedging Instrument
Derivative [Line Items]
Notional amount	246,579	119,709
Asset Derivatives
Derivative assets, gross	237	239
Liability Derivatives
Derivative liabilities, gross	(4,686)	(1,188)
Total risk management derivatives portfolio | Fair Value Hedging | Designated as Hedging Instrument
Derivative [Line Items]
Notional amount	38,858	45,033
Pay-fixed | Designated as Hedging Instrument
Asset Derivatives
Derivative assets, gross	0	0
Liability Derivatives
Derivative liabilities, gross	0	0
Pay-fixed | Not Designated as Hedging Instrument
Derivative [Line Items]
Notional amount	97,808	56,817
Asset Derivatives
Derivative assets, gross	0	0
Liability Derivatives
Derivative liabilities, gross	0	0
Pay-fixed | Fair Value Hedging | Designated as Hedging Instrument
Derivative [Line Items]
Notional amount	5,582	4,347
Receive-fixed | Designated as Hedging Instrument
Asset Derivatives
Derivative assets, gross	0	0
Liability Derivatives
Derivative liabilities, gross	0	0
Receive-fixed | Not Designated as Hedging Instrument
Derivative [Line Items]
Notional amount	99,799	56,874
Asset Derivatives
Derivative assets, gross	1	0
Liability Derivatives
Derivative liabilities, gross	(4,525)	(1,131)
Receive-fixed | Fair Value Hedging | Designated as Hedging Instrument
Derivative [Line Items]
Notional amount	33,276	40,686
Basis | Not Designated as Hedging Instrument
Derivative [Line Items]
Notional amount	41,250	250
Asset Derivatives
Derivative assets, gross	25	152
Liability Derivatives
Derivative liabilities, gross	0	0
Foreign currency | Not Designated as Hedging Instrument
Derivative [Line Items]
Notional amount	300	336
Asset Derivatives
Derivative assets, gross	0	25
Liability Derivatives
Derivative liabilities, gross	(98)	(34)
Pay-fixed swaption | Not Designated as Hedging Instrument
Derivative [Line Items]
Notional amount	5,286	4,341
Asset Derivatives
Derivative assets, gross	204	52
Liability Derivatives
Derivative liabilities, gross	(18)	(2)
Receive-fixed swaption | Not Designated as Hedging Instrument
Derivative [Line Items]
Notional amount	2,136	1,091
Asset Derivatives
Derivative assets, gross	7	10
Liability Derivatives
Derivative liabilities, gross	(45)	(21)
Mortgage commitment derivatives
Derivative [Line Items]
Notional amount	55,706	182,386
Asset Derivatives
Netting adjustment	0	0
Derivative assets	89	169
Liability Derivatives
Netting adjustment	0	0
Derivatives liabilities at fair value	(78)	(197)
Mortgage commitments to purchase whole loans
Derivative [Line Items]
Notional amount	2,596	13,192
Asset Derivatives
Derivative assets	4	17
Liability Derivatives
Derivatives liabilities at fair value	(8)	(5)
Forward contracts to purchase mortgage-related securities
Derivative [Line Items]
Notional amount	17,808	58,021
Asset Derivatives
Derivative assets	50	83
Liability Derivatives
Derivatives liabilities at fair value	(57)	(34)
Forward contracts to sell mortgage-related securities
Derivative [Line Items]
Notional amount	35,302	111,173
Asset Derivatives
Derivative assets	35	69
Liability Derivatives
Derivatives liabilities at fair value	(13)	(158)
Credit enhancement derivatives
Derivative [Line Items]
Notional amount	23,784	19,256
Asset Derivatives
Derivative assets	3	0
Liability Derivatives
Derivatives liabilities at fair value	$ (66)	$ (21)