Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Net income	$ 549,779	$ 527,100	$ 542,939
Unrealized investment gains (losses):
Total unrealized investment gains (losses)	553,801	(1,166,032)	1,283,062
Less applicable (taxes) benefits	(193,820)	408,092	(448,985)
Unrealized gains (losses) on investments, net of tax	359,981	(757,940)	834,077
Unrealized gains (losses) attributable to deferred acquisition costs	(2,412)	8,682	(6,200)
Less applicable (taxes) benefits	845	(3,039)	2,170
Unrealized gains (losses) attributable to deferred acquisition costs, net of tax	(1,567)	5,643	(4,030)
Foreign exchange translation adjustments, other than securities	2,178	(20,651)	(10,770)
Less applicable (taxes) benefits	(838)	6,892	3,290
Foreign exchange translation adjustments, other than securities, net of tax	1,340	(13,759)	(7,480)
Pension adjustments:
Amortization of pension costs	10,168	14,586	10,285
Plan amendments	0	(2,104)	0
Experience gain (loss)	(31,902)	(11,632)	(65,817)
Pension adjustments	(21,734)	850	(55,532)
Less applicable (taxes) benefits	7,607	(299)	19,436
Pension adjustments, net of tax	(14,127)	551	(36,096)
Other comprehensive income (loss)	345,627	(765,505)	786,471
Comprehensive income (loss)	895,406	(238,405)	1,329,410
Securities
Unrealized investment gains (losses):
Unrealized holding gains (losses) arising during period	544,886	(1,163,417)	1,312,548
Reclassification adjustment for (gains) losses on securities included in net income	10,645	9,478	(23,170)
Reclassification adjustment for amortization of (discount) premium	(4,185)	(6,346)	(8,621)
Foreign exchange adjustment on securities recorded at fair value	312	(3,010)	(1,567)
Total unrealized investment gains (losses)	551,658	(1,163,295)	1,279,190
Other Investments
Unrealized investment gains (losses):
Unrealized holding gains (losses) arising during period	2,503	(1,635)	4,473
Reclassification adjustment for (gains) losses on securities included in net income	(360)	(1,102)	(601)
Total unrealized investment gains (losses)	$ 2,143	$ (2,737)	$ 3,872

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