Derivative Instruments - FV Gains and Losses (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Derivative Instruments, Gain (Loss) [Line Items]
Derivative fair value gains (losses), net	$ 2,991	$ 558	$ (2,832)
Net accrual of periodic settlements	$ 29,423	$ 29,587	$ 24,866
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Changes in fair value, gain (loss)	Changes in fair value, gain (loss)	Changes in fair value, gain (loss)
Pay-fixed
Derivative Instruments, Gain (Loss) [Line Items]
Derivative fair value gains (losses), net	$ 5,541	$ 2,207	$ (2,764)
Receive-fixed
Derivative Instruments, Gain (Loss) [Line Items]
Derivative fair value gains (losses), net	(4,788)	(1,783)	2,226
Basis
Derivative Instruments, Gain (Loss) [Line Items]
Derivative fair value gains (losses), net	(143)	(51)	43
Foreign currency
Derivative Instruments, Gain (Loss) [Line Items]
Derivative fair value gains (losses), net	(87)	(26)	23
Pay-fixed swaption
Derivative Instruments, Gain (Loss) [Line Items]
Derivative fair value gains (losses), net	142	38	(146)
Receive-fixed swaption
Derivative Instruments, Gain (Loss) [Line Items]
Derivative fair value gains (losses), net	(19)	(217)	595
Futures
Derivative Instruments, Gain (Loss) [Line Items]
Derivative fair value gains (losses), net	(1)	1	(76)
Risk management derivatives
Derivative Instruments, Gain (Loss) [Line Items]
Derivative fair value gains (losses), net	380	185	(360)
Net accrual of periodic settlements	(265)	16	(261)
Mortgage commitment derivatives
Derivative Instruments, Gain (Loss) [Line Items]
Derivative fair value gains (losses), net	2,708	551	(2,654)
Credit enhancement derivatives
Derivative Instruments, Gain (Loss) [Line Items]
Derivative fair value gains (losses), net	$ (97)	$ (178)	$ 182

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)(1)
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