OTHER COMPREHENSIVE INCOME (LOSS) (DETAILS) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Before Tax Amount
Other Comprehensive Income (Loss), before Tax	$ 69,950	$ (156,244)	$ (174,138)
Tax (Expense) Benefit
Other Comprehensive Income (Loss), Tax	(3,326)	13,353	10,739
Net of Tax Amount
Adjustment for reclassification of net realized investment losses and OTTI losses recognized in net income	62,190	144,991	(114,470)
Other Comprehensive Income (Loss), Net of Tax	66,624	(142,891)	(163,399)
Unrealized gains (losses) on available for sale investments, net of tax [Member]
Before Tax Amount
Unrealized investment gains arising during the year	10,165	(280,512)	(22,704)
Adjustment for reclassification of net realized investment losses and OTTI losses recognized in net income	60,423	145,766	(141,172)
Other Comprehensive Income (Loss), before Tax	70,588	(134,746)	(163,876)
Tax (Expense) Benefit
Unrealized investment gains arising during the year	(5,093)	14,128	(15,963)
Adjustment for reclassification of net realized investment losses and OTTI losses recognized in net income	1,767	(775)	26,702
Other Comprehensive Income (Loss), Tax	(3,326)	13,353	10,739
Net of Tax Amount
Unrealized investment gains arising during the year	5,072	(266,384)	(38,667)
Adjustment for reclassification of net realized investment losses and OTTI losses recognized in net income	62,190	144,991	(114,470)
Other Comprehensive Income (Loss), Net of Tax	67,262	(121,393)	(153,137)
Accumulated Other-than-Temporary Impairment, net of tax [Member]
Before Tax Amount
Other Comprehensive Income (Loss), before Tax	0	0	0
Tax (Expense) Benefit
Other Comprehensive Income (Loss), Tax	0	0	0
Net of Tax Amount
Other Comprehensive Income (Loss), Net of Tax	0	0	0
Cumulative foreign currency translation adjustments, net of tax [Member]
Before Tax Amount
Other Comprehensive Income (Loss), before Tax	(638)	(21,498)	(10,262)
Tax (Expense) Benefit
Other Comprehensive Income (Loss), Tax	0	0	0
Net of Tax Amount
Other Comprehensive Income (Loss), Net of Tax	$ (638)	$ (21,498)	$ (10,262)