Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Net income before noncontrolling interests	$ 683,985	$ 649,066	$ 553,337
Other comprehensive gain (loss):
Change in unrealized translation adjustments	37,166	(112,099)	64,706
Change in unrealized investment gains (losses), net of taxes	215,902	(252,327)	(51,752)
Other comprehensive gain (loss)	253,068	(364,426)	12,954
Comprehensive income	937,053	284,640	566,291
Comprehensive income to the noncontrolling interest	(2,144)	(8,271)	(4,262)
Comprehensive income to common stockholders	$ 934,909	$ 276,369	$ 562,029