CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Net income	$ 105,318	$ 52,394	$ 207,630	$ 11,254
Other comprehensive income (loss):
Foreign currency translation	(284)	100	(158)	135
Unrealized gain (loss) on marketable securities, net of tax	458	102	1,139	(403)
Defined benefit pension obligations, net of tax	108	111	219	222
Other comprehensive income (loss)	282	313	1,200	(46)
Comprehensive income	$ 105,600	$ 52,707	$ 208,830	$ 11,208

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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