REINSURANCE - Life Insurance In-Force and Effect of Reinsurance on Premiums Written and Earned (Details) - USD ($) $ in Thousands	1 Months Ended	11 Months Ended	12 Months Ended
	Jan. 31, 2015	Dec. 31, 2015	Dec. 31, 2017	Dec. 31, 2016
Life insurance in-force
Direct life insurance in-force	$ 0	$ 727,705,256	$ 751,512,468	$ 739,248,680
Amounts assumed from other companies	0	39,546,742	110,205,190	116,265,430
Amounts ceded to other companies	0	(368,142,294)	(328,377,398)	(348,994,650)
Net life insurance in-force	$ 0	$ 399,109,704	$ 533,340,260	$ 506,519,460
Percentage of amount assumed to net	0.00%	9.90%	21.00%	23.00%
Effect of reinsurance on premiums written and earned
Gross Amount		$ 2,674,614	$ 3,017,685	$ 2,929,767
Ceded to Other Companies		(1,154,978)	(1,360,735)	(1,314,716)
Assumed from Other Companies		333,436	459,734	478,164
Net Amount		1,853,072	2,116,684	2,093,215
Reinsurance receivables			5,100,000	5,300,000
Ceded benefits which are recoverable from reinsurers			96,600	87,900
Receivables related to insurance assumed			65,100	64,500
Life insurance
Effect of reinsurance on premiums written and earned
Gross Amount		2,360,643	2,655,846	2,610,682
Ceded to Other Companies		(983,143)	(1,151,175)	(1,126,915)
Assumed from Other Companies		308,280	435,113	454,999
Net Amount		1,685,780	1,939,784	1,938,766
Annuity policy fees	$ 13,900	152,800	173,500	160,400
Accident/health insurance
Effect of reinsurance on premiums written and earned
Gross Amount		70,243	51,991	58,076
Ceded to Other Companies		(36,871)	(33,051)	(36,935)
Assumed from Other Companies		18,252	14,945	17,439
Net Amount		51,624	33,885	38,580
Property and liability insurance
Effect of reinsurance on premiums written and earned
Gross Amount		243,728	309,848	261,009
Ceded to Other Companies		(134,964)	(176,509)	(150,866)
Assumed from Other Companies		6,904	9,676	5,726
Net Amount		$ 115,668	$ 143,015	115,869
Predecessor
Effect of reinsurance on premiums written and earned
Gross Amount	230,790
Ceded to Other Companies	(89,956)
Assumed from Other Companies	31,076
Net Amount	171,910
Predecessor | Life insurance
Effect of reinsurance on premiums written and earned
Gross Amount	204,185
Ceded to Other Companies	(74,539)
Assumed from Other Companies	28,601
Net Amount	158,247
Annuity policy fees	13,900			$ 160,400
Predecessor | Accident/health insurance
Effect of reinsurance on premiums written and earned
Gross Amount	6,846
Ceded to Other Companies	(4,621)
Assumed from Other Companies	1,809
Net Amount	4,034
Predecessor | Property and liability insurance
Effect of reinsurance on premiums written and earned
Gross Amount	19,759
Ceded to Other Companies	(10,796)
Assumed from Other Companies	666
Net Amount	$ 9,629