DEBT AND OTHER OBLIGATIONS - Non-Recourse Funding Obligations Outstanding (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Outstanding Principal	$ 3,079,040	$ 2,884,040
Carrying value	3,082,753	2,888,329
Golden Gate Captive Insurance Company (Golden Gate)
Debt Instrument [Line Items]
Outstanding Principal	2,028,000	1,883,000
Carrying value	$ 2,028,000	$ 1,883,000
Year-to-Date Weighted- Avg Interest Rate	4.70%	4.75%
Golden Gate II Captive Insurance Company (Golden Gate II)
Debt Instrument [Line Items]
Outstanding Principal	$ 329,949	$ 329,949
Carrying value	$ 274,955	$ 273,535
Year-to-Date Weighted- Avg Interest Rate	5.06%	4.24%
Golden Gate V Vermont Captive Insurance Company (Golden Gate V)
Debt Instrument [Line Items]
Outstanding Principal	$ 720,000	$ 670,000
Carrying value	$ 777,527	$ 729,454
Year-to-Date Weighted- Avg Interest Rate	5.12%	5.12%
MONY Life Insurance Company
Debt Instrument [Line Items]
Outstanding Principal	$ 1,091	$ 1,091
Carrying value	$ 2,271	$ 2,340
Year-to-Date Weighted- Avg Interest Rate	6.19%	6.19%