ALLOWANCE FOR CREDIT LOSSES - Allowance for Loan Losses Roll Forward (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Allowance for credit losses
Allowance for loan losses at beginning of period	$ 14,075	$ 17,890	$ 15,994	$ 19,648
Gross credit losses	(2,068)	(2,586)	(6,861)	(8,381)
Gross recoveries	405	489	1,321	1,656
NCLs	1,663	2,097	5,540	6,725
Net reserve builds (releases)	43	(492)	(247)	(1,573)
Net specific reserve builds (releases)	(124)	(30)	(441)	(205)
Total provision for credit losses	1,582	1,575	4,852	4,947
Other, net	(368)	(453)	(1,680)	(955)
Allowance for loan losses at the end of year	13,626	16,915	13,626	16,915
Allowance for credit losses on unfunded lending commitments
Allowance for credit losses on unfunded lending commitments at beginning of year	973	1,176	1,063	1,229
Provision (release) for unfunded lending commitments	65	(30)	(20)	(88)
Other, net	(2)	(6)	(7)	(1)
Allowance for credit losses on unfunded lending commitments at end of year	1,036	1,140	1,036	1,140
Total allowance for loans, leases, and unfunded lending commitments at end of period	$ 14,662	$ 18,055	$ 14,662	$ 18,055