Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Net income	$ 1,454,494	$ 549,779	$ 527,100
Unrealized investment gains (losses):
Total unrealized investment gains (losses)	921,421	553,801	(1,166,032)
Less applicable (taxes) benefits	(322,553)	(193,820)	408,092
Unrealized gains (losses) on investments, net of tax	598,868	359,981	(757,940)
Unrealized gains (losses) attributable to deferred acquisition costs	(538)	(2,412)	8,682
Less applicable (taxes) benefits	188	845	(3,039)
Unrealized gains (losses) attributable to deferred acquisition costs, net of tax	(350)	(1,567)	5,643
Foreign exchange translation adjustments, other than securities	11,389	2,178	(20,651)
Less applicable (taxes) benefits	(2,937)	(838)	6,892
Foreign exchange translation adjustments, other than securities, net of tax	8,452	1,340	(13,759)
Pension adjustments:
Amortization of pension costs	12,436	10,168	14,586
Plan amendments	0	0	(2,104)
Experience gain (loss)	(31,933)	(31,902)	(11,632)
Pension adjustments	(19,497)	(21,734)	850
Less applicable (taxes) benefits	6,827	7,607	(299)
Pension adjustments, net of tax	(12,670)	(14,127)	551
Other comprehensive income (loss)	594,300	345,627	(765,505)
Comprehensive income (loss)	2,048,794	895,406	(238,405)
Securities
Unrealized investment gains (losses):
Unrealized holding gains (losses) arising during period	950,088	544,886	(1,163,417)
Reclassification adjustment for (gains) losses on securities included in net income	(34,954)	10,645	9,478
Reclassification adjustment for amortization of (discount) premium	(47)	(4,185)	(6,346)
Foreign exchange adjustment on securities recorded at fair value	1,326	312	(3,010)
Total unrealized investment gains (losses)	916,413	551,658	(1,163,295)
Other
Unrealized investment gains (losses):
Unrealized holding gains (losses) arising during period	5,008	2,503	(1,635)
Reclassification adjustment for (gains) losses on securities included in net income	0	(360)	(1,102)
Total unrealized investment gains (losses)	$ 5,008	$ 2,143	$ (2,737)

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