CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE EARNINGS - UNAUDITED - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Statement Of Income And Comprehensive Income [Abstract]
Net earnings	$ 20,239	$ 11,990
Other comprehensive earnings (loss):
Changes in fair market value of derivatives, net of tax	1,235	124
Changes in unrealized pension cost, net of tax	94	1,422
Cumulative translation adjustment, net of tax	(249)	12
Other comprehensive earnings	1,080	1,558
Comprehensive earnings	$ 21,319	$ 13,548

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

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