INVESTMENT OPERATIONS - Schedule of Amortized Cost and Fair Value of Available-for-Sale and Held-to-Maturity Fixed Maturities, by Expected Maturity (Details) - Successor - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Held-to-maturity Securities, Fair Value
Fair Value	$ 2,733,340	$ 515,000
Fixed maturities
Available-for-sale, Amortized Cost
Due in one year or less	565,117
Due after one year through five years	7,210,168
Due after five years through ten years	7,783,685
Due after ten years	21,633,894
Total	37,192,864
Available-for-sale Fair Value
Due in one year or less	566,482
Due after one year through five years	7,180,919
Due after five years through ten years	7,651,075
Due after ten years	20,145,001
Total	35,543,477
Held-to-maturity Securities, Amortized Cost
Due in one year or less	0
Due after one year through five years	0
Due after five years through ten years	0
Due after ten years	2,770,177
Amortized Cost	2,770,177	593,314
Held-to-maturity Securities, Fair Value
Due in one year or less	0
Due after one year through five years	0
Due after five years through ten years	0
Due after ten years	2,733,340
Fair Value	$ 2,733,340	$ 515,000