Consolidated Statement of Comprehensive Income (unaudited) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Statement of Comprehensive Income [Abstract]
Net change in unrealized gains on securities, taxes	$ (8,362)	$ 15,262	$ (85,700)	$ 103,490
Net change in other-than-temporary impairment gains, taxes	(165)	1,031	405	1,663
Net change in foreign currency translation, taxes	498	2,543	(1,157)	4,486
Net change in pension plan curtailment and amortization of pension and postretirement unrecognized net periodic benefit cost, taxes	$ (96)	$ (1,481)	$ (35,966)	$ (4,299)