Condensed Consolidated Statements of Comprehensive Earnings - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Statement of Comprehensive Income [Abstract]
Net earnings	$ 34,667	$ 32,727	$ 56,185	$ 51,067
Other comprehensive earnings
Unrealized gain on marketable securities, net of tax	11,525	4,497	3,942	9,082
Other comprehensive earnings	11,525	4,497	3,942	9,082
Comprehensive earnings	$ 46,192	$ 37,224	$ 60,127	$ 60,149

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

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