CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Statement of Comprehensive Income [Abstract]
Net income	$ 95,686	$ 129,460	$ 115,542	$ 177,846
Other comprehensive income, net of tax:
Unrealized investment gains arising during the period	76,243	63,685	143,953	202,319
Adjustment for reclassification of net realized investment (gains) losses and OTTI losses recognized in net income	(1,503)	(14,019)	23,458	45,263
Unrealized investment gains arising during the period, net of reclassification adjustment	74,740	49,666	167,411	247,582
Foreign currency translation adjustment	8,867	(4,224)	38,736	3,972
Total other comprehensive income, net of tax	83,607	45,442	206,147	251,554
Comprehensive income	$ 179,293	$ 174,902	$ 321,689	$ 429,400