Securitization Activities and Consolidation - Non-Consolidated VIEs (Details) - USD ($) $ in Millions	Sep. 30, 2020	Jan. 01, 2020	Dec. 31, 2019
Assets [Abstract]
Investments in securities, at fair value	$ 71,702		$ 75,711
Accrued interest receivable, net	7,583		6,848
Derivative Assets, net	1,282		844
Other Assets	40,051	$ 22,992	22,799
Liabilities [Abstract]
Derivative Liabilities, net	613		372
Other Liabilities	10,231	$ 8,046	8,042
Total assets	2,454,071		2,193,780
Variable Interest Entity, Not Primary Beneficiary
Assets [Abstract]
Investments in securities, at fair value	37,410		37,918
Accrued interest receivable, net	247		212
Derivative Assets, net	49		14
Other Assets	5,474		3,951
Liabilities [Abstract]
Derivative Liabilities, net	50		108
Other Liabilities	4,135		3,761
Maximum Exposure to Loss	372,341		307,820
Total assets	$ 366,496		$ 335,562