Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 105,943	$ 175,841	$ 460,685	$ 278,161
Other comprehensive income (loss), net of tax
Change in net unrealized gains (losses) on securities	(2,569)	(14,395)	181,305	(142,116)
Foreign currency transaction and translation adjustments	(293)	(181)	297	(681)
Defined benefit pension plan adjustment	1,454	1,601	4,365	3,991
Total other comprehensive income (loss), net of tax	(1,408)	(12,975)	185,967	(138,806)
Total comprehensive income	104,535	162,866	646,652	139,355
Less: Comprehensive income attributable to noncontrolling interest	13,759	2,377	11,444	1,781
Total comprehensive income attributable to American National	$ 90,776	$ 160,489	$ 635,208	$ 137,574