CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Comprehensive income (loss)
Net income	$ 204,374	$ 232,190	$ 304,604	$ 377,702
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	(54,677)	43,565	(55,837)	21,352
Net unrealized investment gains (losses)	(368,719)	306,329	(1,002,323)	509,444
Defined benefit pension and postretirement plan adjustments	(29)	849	(500)	1,773
Total other comprehensive income (loss), net of tax	(423,425)	350,743	(1,058,660)	532,569
Total comprehensive income (loss)	$ (219,051)	$ 582,933	$ (754,056)	$ 910,271

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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