DERIVATIVE FINANCIAL INSTRUMENTS - Realized Investment Gains (Losses), All Other Investments (Details) - USD ($) $ in Thousands	1 Months Ended	11 Months Ended	12 Months Ended
	Jan. 31, 2015	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2014
Successor
Realized investment gains (losses) - all other investments
Realized investment gains (losses)		$ (167,359)	$ 67,583
Predecessor
Realized investment gains (losses) - all other investments
Realized investment gains (losses)	$ 73,062			$ 142,016
Modco Trading Portfolio | Successor
Realized investment gains (losses) - all other investments
Realized investment gains (losses)		$ (167,359)	$ 67,583
Modco Trading Portfolio | Predecessor
Realized investment gains (losses) - all other investments
Realized investment gains (losses)	$ 73,062			$ 142,016