Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement Of Income And Comprehensive Income [Abstract]
Net earnings	$ 592,016	$ 619,790	$ 490,383
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustments, net of tax expense (benefit) of $25,731 in 2019, $(13,364) in 2018 and $16,761 in 2017	(26,553)	(32,390)	30,434
Reclassification adjustment for foreign currency realized losses, net of tax of $145 in 2019	535	0	0
Other comprehensive (loss) income	(26,018)	(32,390)	30,434
Comprehensive income	565,998	587,400	520,817
Less comprehensive income attributable to the noncontrolling interest	1,309	718	844
Comprehensive income attributable to shareholders	$ 564,689	$ 586,682	$ 519,973