SHARE-BASED AND OTHER COMPENSATION PROGRAMS - Alliance Bernstein (Details) - Alliance Bernstein - USD ($) $ in Millions	1 Months Ended		12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units purchased during the period (in shares)			9,000,000	11,000,000
Dollar amount paid for Holding Units acquired			$ 220	$ 237
Open-market purchases (in shares)			5,000,000	8,000,000
Open-market purchases, value			$ 117	$ 176
Restricted holding unit awards granted to employees (in shares)	6,100,000	6,100,000	8,300,000	7,000,000
Units issued upon exercise of options (in shares)			1,200,000	400,000
Proceeds from options exercised			$ 20	$ 6
Holding unit-based awards authorized for grant (in shares)	60,000,000		60,000,000
Holding unit-based awards, maximum additional shares authorized for grant (in shares)			30,000,000
Grant of holding units (in shares)			0
Grant of holding units, net of forfeitures (in shares)			6,100,000
Holding unit-based awards available for grant (in shares)	53,900,000		53,900,000