Condensed Consolidated Statements of Comprehensive Earnings - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Statement of Comprehensive Income [Abstract]
Net earnings	$ 21,518	$ 18,340
Other comprehensive (loss) earnings
Unrealized (loss) gain on marketable securities, net of tax	(7,583)	4,585
Other comprehensive (loss) earnings	(7,583)	4,585
Comprehensive earnings	$ 13,935	$ 22,925

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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