Consolidated Statements of Comprehensive Earnings - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Consolidated Statements of Comprehensive Earnings
Net earnings	$ 28,011	$ 15,961	$ 85,100	$ 43,626
Other comprehensive earnings (loss):
Unrealized (loss) gain on marketable securities, net of tax	8	36	(3,364)	386
Other comprehensive earnings (loss)	8	36	(3,364)	386
Comprehensive earnings	$ 28,019	$ 15,997	$ 81,736	$ 44,012

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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