CONDENSED CONSOLIDATED STATEMENT OF COMPREHENSIVE EARNINGS (unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Statement of Comprehensive Income [Abstract]
Net earnings	$ 105,705	$ 131,435
Foreign currency translation adjustments [Abstract]
Foreign currency translation (losses) gains	23,700	52,308
Reclassification of foreign currency translation losses to earnings	25,339	0
Total foreign currency translation adjustment	49,039	52,308
Pension and other postretirement benefit plans [Abstract]
Amortization of actuarial losses included in net periodic pension cost	175	1,939
Amortization of prior service cost included in net periodic pension cost	572	743
Total pension and other postretirement benefit plans	747	2,682
Changes in fair value of cash flow hedges [Abstract]
Unrealized net (losses) gains arising during period	2,594	1,362
Net losses (gains) reclassified into earnings	(230)	(253)
Total cash flow hedges	2,364	1,109
Other comprehensive (loss) earnings	52,150	56,099
Comprehensive earnings	$ 157,855	$ 187,534