SIGNIFICANT TRANSACTIONS - Purchase Consideration (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	May 01, 2018
Life Business
Pro Forma [Abstract]
Revenue	$ 1,242,895	$ 1,370,172	$ 2,556,894	$ 2,751,894
Net income	$ 59,656	$ 120,694	$ 116,687	$ 216,855
Expected Amortization
Remainder of 2018					$ 10,316
2019					20,636
2020					19,546
2021					17,958
2022					16,275
P L I C O
ASSETS
Fixed maturities					12,588,512
Mortgage loans					435,405
Policy loans					131,489
Total investments					13,155,406
Cash					20,669
Accrued investment income					151,610
Reinsurance receivables					337
Value of business acquired					329,630
Other assets					2,542
Total assets					13,660,194
LIABILITIES
Future policy benefits and claims					11,737,086
Unearned premiums					0
Total policy liabilities and accruals					11,737,086
Annuity account balances					1,823,444
Other policyholders' funds					41,954
Other liabilities					57,710
Total liabilities					13,660,194
NET ASSETS ACQUIRED					$ 0