CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE EARNINGS - UNAUDITED - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Statement of Comprehensive Income [Abstract]
Net earnings	$ 12,598	$ 875	$ 32,837	$ 12,865
Other comprehensive earnings (loss):
Changes in fair market value of derivatives, net of tax	705	268	1,940	392
Changes in unrealized pension cost, net of tax	2,082	17,024	2,176	18,446
Cumulative translation adjustment, net of tax	(2,012)	1	(2,261)	13
Other comprehensive earnings	775	17,293	1,855	18,851
Comprehensive earnings	$ 13,373	$ 18,168	$ 34,692	$ 31,716