MONY CLOSED BLOCK OF BUSINESS - Summary of Financial Information of the Policyholder Dividend Obligation (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018	Dec. 31, 2017
Closed block liabilities
Future policy benefits, policyholders’ account balances and other policyholder liabilities	$ 5,611,917	$ 5,679,732
Policyholder dividend obligation	173,147	0	$ 0	$ 160,712
Other liabilities	11,043	22,505
Total closed block liabilities	5,796,107	5,702,237
Closed block assets
Fixed maturities, available-for-sale, at fair value	4,583,161	4,257,437
Mortgage loans on real estate	74,290	75,838
Policy loans	658,971	672,213
Cash	55,960	116,225
Other assets	107,306	136,388
Total closed block assets	5,479,688	5,258,101
Excess of reported closed block liabilities over closed block assets	316,419	444,136
Portion of above representing accumulated other comprehensive income:
Net unrealized investment gains (losses) net of policyholder dividend obligation: $47,972 and $(141,128); and net of income tax: $(10,074) and $61,676	0	(120,528)
Future earnings to be recognized from closed block assets and closed block liabilities	316,419	323,608
Policyholder dividend obligations	47,972	(141,128)
Deferred income tax expense (benefit)	$ (10,074)	$ 61,676