SECURITIZATIONS AND VARIABLE INTEREST ENTITIES - Asset Based Financing (Details) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Variable Interest Entity
Total unconsolidated VIE assets	$ 235,887	$ 243,175
Maximum exposure to unconsolidated VIEs	47,233	47,014
Asset-based financing
Variable Interest Entity
Total unconsolidated VIE assets	62,382	59,839
Maximum exposure to unconsolidated VIEs	26,665	25,939
Commercial and other real estate | Asset-based financing
Variable Interest Entity
Total unconsolidated VIE assets	15,152	15,370
Maximum exposure to unconsolidated VIEs	4,815	5,445
Corporate loans | Asset-based financing
Variable Interest Entity
Total unconsolidated VIE assets	6,862	4,725
Maximum exposure to unconsolidated VIEs	5,731	3,587
Hedge funds and equities | Asset-based financing
Variable Interest Entity
Total unconsolidated VIE assets	449	542
Maximum exposure to unconsolidated VIEs	58	58
Airplanes, ships and other assets | Asset-based financing
Variable Interest Entity
Total unconsolidated VIE assets	39,919	39,202
Maximum exposure to unconsolidated VIEs	$ 16,061	$ 16,849