INTEREST REVENUE AND EXPENSE (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Interest revenue
Loan interest, including fees	$ 47,751	$ 45,682	$ 41,736
Deposits with banks	2,682	2,203	1,635
Securities borrowed and purchased under agreements to resell	6,872	5,492	3,249
Investments, including dividends	9,860	9,494	8,295
Trading account assets	7,672	6,284	5,501
Other interest	1,673	1,673	1,163
Total interest revenue	76,510	70,828	61,579
Interest expense
Deposits	12,633	9,616	6,587
Securities loaned and sold under agreements to repurchase	6,263	4,889	2,661
Trading account liabilities	1,308	1,001	638
Short-term borrowings	2,465	2,209	1,059
Long-term debt	6,494	6,551	5,573
Total interest expense	29,163	24,266	16,518
Net interest revenue	47,347	46,562	45,061
Provision for loan losses	8,218	7,354	7,503
Net interest revenue after provision for loan losses	39,129	39,208	37,558
Insurance fees and charges	$ 781	$ 1,182	$ 1,249