CONSOLIDATED STATEMENTS OF COMPREHENSIVE EARNINGS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Net earnings	$ 677,918	$ 570,267	$ 811,665
Foreign currency translation adjustments [Abstract]
Foreign currency translation gains (losses)	(5,025)	(59,970)	143,064
Reclassification of foreign currency translation losses (gains) to earnings	25,339	0	3,992
Total foreign currency translation adjustments	20,314	(59,970)	147,056
Pension and other postretirement benefit plans [Abstract]
Actuarial gains (losses)	47	(13,107)	12,439
Prior service credit (cost)	(1,818)	(14,661)	3,136
Amortization of actuarial losses including in net periodic pension cost	596	3,829	5,267
Amortization of prior service costs included in net periodic pension cost	2,141	2,875	3,007
Settlement and curtailment	806	9,926	(2,462)
Total pension and other postretirement benefit plans	5,408	(11,138)	21,387
Changes in fair value of cash flow hedges [Abstract]
Unrealized net (losses) gains	1,495	1,158	(1,801)
Net (gains) losses reclassified into earnings	(147)	1,541	(590)
Total cash flow hedges	1,348	2,699	(2,391)
Other	0	0	(1,485)
Other comprehensive earnings (loss), net of tax	27,070	(68,409)	164,567
Comprehensive earnings	$ 704,988	$ 501,858	$ 976,232