SECURITIZATIONS AND VARIABLE INTEREST ENTITIES - Asset Based Financing (Details) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Variable Interest Entity
Total unconsolidated VIE assets	$ 244,858	$ 243,175
Maximum exposure to unconsolidated VIEs	51,845	47,014
Asset-based financing
Variable Interest Entity
Total unconsolidated VIE assets	64,178	59,839
Maximum exposure to unconsolidated VIEs	29,875	25,939
Commercial and other real estate | Asset-based financing
Variable Interest Entity
Total unconsolidated VIE assets	18,098	15,370
Maximum exposure to unconsolidated VIEs	6,949	5,445
Corporate loans | Asset-based financing
Variable Interest Entity
Total unconsolidated VIE assets	6,815	4,725
Maximum exposure to unconsolidated VIEs	5,764	3,587
Hedge funds and equities | Asset-based financing
Variable Interest Entity
Total unconsolidated VIE assets	416	542
Maximum exposure to unconsolidated VIEs	54	58
Airplanes, ships and other assets | Asset-based financing
Variable Interest Entity
Total unconsolidated VIE assets	38,849	39,202
Maximum exposure to unconsolidated VIEs	$ 17,108	$ 16,849