Condensed Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Net income	$ 760,790	$ 701,466	$ 1,454,494
Unrealized gains (losses) on fixed maturities:
Total unrealized investment gains (losses)	1,958,165	(1,434,918)	921,421
Less applicable tax (expense) benefit	(411,213)	301,327	(322,553)
Unrealized gains (losses) on investments, net of tax	1,546,952	(1,133,591)	598,868
Foreign exchange translation adjustments, other than securities	7,042	(12,417)	11,389
Less applicable tax (expense) benefit	(1,479)	2,610	(2,937)
Foreign exchange translation adjustments, other than securities, net of tax	5,563	(9,807)	8,452
Deferred acquisition costs:
Unrealized gains (losses) attributable to deferred acquisition costs	(2,218)	5,549	(538)
Less applicable tax (expense) benefit	465	(1,165)	188
Unrealized gains (losses) attributable to deferred acquisition costs, net of tax	(1,753)	4,384	(350)
Pension:
Amortization of pension costs	8,474	15,095	12,436
Plan amendments	0	(2,377)	0
Experience gain (loss)	(40,636)	30,591	(31,933)
Pension adjustments	(32,162)	43,309	(19,497)
Less applicable tax (expense) benefit	6,755	(9,094)	6,827
Pension adjustments, net of tax	(25,407)	34,215	(12,670)
Other comprehensive income (loss)	1,525,355	(1,104,799)	594,300
Comprehensive income (loss)	2,286,145	(403,333)	2,048,794
Securities
Unrealized gains (losses) on fixed maturities:
Unrealized holding gains (losses) arising during period	1,959,596	(1,426,581)	950,088
Reclassifications adjustments included in net income	(13,837)	(1,758)	(35,001)
Foreign exchange adjustment on securities recorded at fair value	1,151	(1,424)	1,326
Total unrealized investment gains (losses)	1,946,910	(1,429,763)	916,413
Other investments
Unrealized gains (losses) on fixed maturities:
Total unrealized investment gains (losses)	$ 11,255	$ (5,155)	$ 5,008