Consolidations and Transfers of Financial Assets - Unconsolidated VIEs (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Variable Interest Entities [Line Items]
Investments in securities, at fair value	$ 51,872	$ 50,825
Other assets	13,240	13,387
Other liabilities	(13,135)	(13,206)
Assets	4,329,380	4,305,288
Total unpaid principal balance of mortgage loans	4,100,280	4,075,598
Multifamily
Variable Interest Entities [Line Items]
Total unpaid principal balance of mortgage loans	455,555	431,440
Multifamily | Unconsolidated VIEs
Variable Interest Entities [Line Items]
Total unpaid principal balance of mortgage loans	455,600
Mortgage-related | Unconsolidated VIEs
Variable Interest Entities [Line Items]
Investments in securities, at fair value	2,735	3,353
Other assets	37	40
Other liabilities	(43)	(45)
Net carrying amount	2,729	3,348
Maximum exposure to loss	224,000	240,000
Assets	230,000	240,000
Partnership interest LIHTC | Unconsolidated VIEs
Variable Interest Entities [Line Items]
Net carrying amount	474	424
Maximum exposure to loss	478	427
Assets	5,500	4,300
Total available-for-sale securities | Unconsolidated VIEs
Variable Interest Entities [Line Items]
Maximum exposure to loss	20,100	16,900
Assets	$ 20,100	$ 17,000