Variable Interest Entities and Securitization Activities - Non-Consolidated VIEs (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Variable Interest Entity
Carrying value of variable interests—Assets	$ 1,222,233	$ 1,188,140
Additional VIE assets owned	13,339	15,392
Carrying value of variable interests—Liabilities	1,118,158	1,081,542
Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity
VIE assets (UPB)	116,627	146,071
MABS
Variable Interest Entity
VIE assets (UPB)	116,627	146,071
Maximum exposure to loss	14,012	18,833
MABS | Assets | Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity
Carrying value of variable interests—Assets	13,005	18,062
MABS | Debt and equity interests
Variable Interest Entity
Maximum exposure to loss	13,005	18,062
MABS | Debt and equity interests | Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity
Carrying value of variable interests—Assets	13,005	18,062
MABS | Derivative and other contracts
Variable Interest Entity
Maximum exposure to loss	0	0
MABS | Derivative and other contracts | Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity
Carrying value of variable interests—Assets	0	0
MABS | Commitments, guarantees and other
Variable Interest Entity
Maximum exposure to loss	1,007	771
MABS | Derivative and other contracts | Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity
Carrying value of variable interests—Liabilities	0	0
CDO
Variable Interest Entity
VIE assets (UPB)	1,379	667
Maximum exposure to loss	157	129
CDO | Assets | Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity
Carrying value of variable interests—Assets	157	129
CDO | Debt and equity interests
Variable Interest Entity
Maximum exposure to loss	157	129
CDO | Debt and equity interests | Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity
Carrying value of variable interests—Assets	157	129
CDO | Derivative and other contracts
Variable Interest Entity
Maximum exposure to loss	0	0
CDO | Derivative and other contracts | Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity
Carrying value of variable interests—Assets	0	0
CDO | Commitments, guarantees and other
Variable Interest Entity
Maximum exposure to loss	0	0
CDO | Derivative and other contracts | Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity
Carrying value of variable interests—Liabilities	0	0
MTOB
Variable Interest Entity
VIE assets (UPB)	6,465	6,089
Maximum exposure to loss	4,382	4,100
MTOB | Assets | Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity
Carrying value of variable interests—Assets	6	5
MTOB | Debt and equity interests
Variable Interest Entity
Maximum exposure to loss	0	0
MTOB | Debt and equity interests | Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity
Carrying value of variable interests—Assets	0	0
MTOB | Derivative and other contracts
Variable Interest Entity
Maximum exposure to loss	4,382	4,100
MTOB | Derivative and other contracts | Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity
Carrying value of variable interests—Assets	6	5
MTOB | Commitments, guarantees and other
Variable Interest Entity
Maximum exposure to loss	0	0
MTOB | Derivative and other contracts | Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity
Carrying value of variable interests—Liabilities	1	0
OSF
Variable Interest Entity
VIE assets (UPB)	2,043	2,086
Maximum exposure to loss	1,449	1,459
OSF | Assets | Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity
Carrying value of variable interests—Assets	1,449	1,459
OSF | Debt and equity interests
Variable Interest Entity
Maximum exposure to loss	1,449	1,459
OSF | Debt and equity interests | Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity
Carrying value of variable interests—Assets	1,449	1,459
OSF | Derivative and other contracts
Variable Interest Entity
Maximum exposure to loss	0	0
OSF | Derivative and other contracts | Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity
Carrying value of variable interests—Assets	0	0
OSF | Commitments, guarantees and other
Variable Interest Entity
Maximum exposure to loss	0	0
OSF | Derivative and other contracts | Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity
Carrying value of variable interests—Liabilities	0	0
Other
Variable Interest Entity
VIE assets (UPB)	54,186	52,111
Maximum exposure to loss	16,883	16,943
Other | Assets | Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity
Carrying value of variable interests—Assets	12,697	12,345
Other | Debt and equity interests
Variable Interest Entity
Maximum exposure to loss	11,055	10,339
Other | Debt and equity interests | Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity
Carrying value of variable interests—Assets	11,055	10,339
Other | Derivative and other contracts
Variable Interest Entity
Maximum exposure to loss	4,374	5,599
Other | Derivative and other contracts | Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity
Carrying value of variable interests—Assets	1,642	2,006
Other | Commitments, guarantees and other
Variable Interest Entity
Maximum exposure to loss	1,454	1,005
Other | Derivative and other contracts | Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity
Carrying value of variable interests—Liabilities	$ 280	$ 362