GOODWILL - Goodwill Rollforward (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended		12 Months Ended	6 Months Ended	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013	Jun. 30, 2013 Consumer Banking	Sep. 30, 2014 Consumer Banking	Sep. 30, 2013 Consumer Banking	Sep. 30, 2014 Commercial Banking	Sep. 30, 2013 Commercial Banking
Goodwill [Roll Forward]
Beginning balance			$ 6,876	$ 11,311	$ 11,311	$ 6,393	$ 2,136	$ 6,393	$ 4,740	$ 4,918
Impairment losses based on results of interim impairment testing	0	0	0	(4,435)	(4,400)	(4,400)		(4,435)		0
Transfers				0				178		(178)
Adjustments			0				0		0
Ending balance	$ 6,876	$ 6,876	$ 6,876	$ 6,876	$ 6,876		$ 2,136	$ 2,136	$ 4,740	$ 4,740