ORGANIZATION - Narrative (Details) $ in Millions	9 Months Ended	12 Months Ended
Sep. 30, 2020 USD ($) segment	Dec. 31, 2019 USD ($)
Organization Basis Of Presentation [Line Items]
Number of reportable segments \| segment	4
U.S. Financial Life Insurance Company and MONY Life Insurance Company of the Americas, Ltd
Organization Basis Of Presentation [Line Items]
Investment impairment \| $	$ 39	$ 105
Alliance Bernstein
Organization Basis Of Presentation [Line Items]
Economic interest	65.00%	65.00%

The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109226691&loc=d3e2921-110230

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=109226348&loc=d3e2420-110228

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration