MONY CLOSED BLOCK OF BUSINESS - Schedule of Reconciliation of the Policyholder Dividend Obligation (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Movement in Closed Block Dividend Obligation [Roll Forward]
Policyholder dividend obligation, beginning balance	$ 160,712	$ 31,932
Applicable to net revenue (losses)	(33,014)	(55,241)
Change in net unrealized investment gains (losses) allocated to policyholder dividend obligation	(127,698)	184,021
Policyholder dividend obligation, ending balance	$ 0	$ 160,712

Amount of increase (decrease) in the closed block dividend obligation from the unrealized gain (loss) on investments allocated to the closed block.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 805
-Section 35
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=6487164&loc=d3e30481-158566

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 805
-Section 55
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=84167291&loc=d3e31071-158570

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 805
-Section 50
-Paragraph 3
-Subparagraph (b)(10)
-URI http://asc.fasb.org/extlink&oid=6487222&loc=d3e30806-158569

+ Details

Name:	us-gaap_ClosedBlockDividendObligationChangeInUnrealizedInvestmentGainsLosses
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of increase (decrease) in the closed block dividend obligation from the effect on dividends to policyholders on the net results of operations for the period of the closed block.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 805
-Section 50
-Paragraph 3
-Subparagraph (b)(10)
-URI http://asc.fasb.org/extlink&oid=6487222&loc=d3e30806-158569

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 805
-Section 55
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=84167291&loc=d3e31071-158570

+ Details

Name:	us-gaap_ClosedBlockDividendObligationIncreaseDecreaseForEffectOfOperatingResults
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The liability as of the balance sheet date for the excess of the cumulative actual closed block earnings over the cumulative expected (actuarially determined) closed block earnings (each) for the period from the actuarial calculation date to the date of measurement. The excess will result in future dividends to closed block policyholders, unless offset by less favorable than expected future performance of the closed block. The policyholder dividend obligation, which may not have a negative balance, recognizes that a portion of earnings in certain cases will not inure to the stockholders of the insurance entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 805
-Section 55
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=84167291&loc=d3e31071-158570

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 805
-Section 50
-Paragraph 3
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=6487222&loc=d3e30806-158569

+ Details

Name:	us-gaap_ClosedBlockLiabilitiesPolicyholderDividendObligation
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

Name:	us-gaap_MovementInClosedBlockDividendObligationRollForward
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration