Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Statement of Comprehensive Income [Abstract]
Net income before noncontrolling interests	$ 504,107	$ 649,603	$ 505,301
Other comprehensive income:
Change in unrealized translation adjustments	(124,744)	(62,125)	(23,848)
Change in unrealized investment gains (losses), net of taxes	(125,542)	49,666	(261,064)
Change in unrecognized pension obligation, net of taxes	0	6,651	8,700
Other comprehensive loss	(250,286)	(5,808)	(276,212)
Comprehensive income	253,821	643,795	229,089
Comprehensive income to the noncontrolling interest	(375)	(752)	(5,404)
Comprehensive income to common shareholders	$ 253,446	$ 643,043	$ 223,685