Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Statement of Comprehensive Income [Abstract]
Net earnings	$ 19,768	$ 18,783
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustment	781	(1,089)
Unrealized loss on cash flow hedge	(3,107)	0
Change in postretirement benefit plans	(579)	5
Other comprehensive loss	(2,905)	(1,084)
Comprehensive income	$ 16,863	$ 17,699

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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