DISCONTINUED OPERATIONS - Transactions Prior to Distribution (Details) - Alliance Bernstein - Discontinued Operations $ in Millions	12 Months Ended
	Dec. 31, 2018 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total investment management and service fees	$ 3,243
Base fees
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total investment management and service fees	2,156
Performance-based fees
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total investment management and service fees	118
Research services
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total investment management and service fees	439
Distribution services
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total investment management and service fees	419
Shareholder services
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total investment management and service fees	76
Other revenues - other
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total investment management and service fees	$ 35