CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
Net income (loss)	$ 290,298	$ 105,318	$ (430,344)	$ 207,630
Other comprehensive loss:
Foreign currency translation	993	(284)	2,553	(158)
Unrealized (loss) gain on marketable securities, net of tax	(529)	458	125	1,139
Defined benefit pension obligations, net of tax	220	108	441	219
Other comprehensive income	684	282	3,119	1,200
Comprehensive income (loss)	$ 290,982	$ 105,600	$ (427,225)	$ 208,830

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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