CONDENSED CONSOLIDATED STATEMENT OF COMPREHENSIVE EARNINGS (unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Statement of Comprehensive Income [Abstract]
Net earnings	$ 178,912	$ 130,084	$ 515,217	$ 347,730
Foreign currency translation adjustments [Abstract]
Foreign currency translation gains (losses) during period	93,269	11,489	159,340	(21,734)
Reclassification of foreign currency translation losses to earnings upon sale of subsidiary	0	0	3,875	0
Total foreign currency translation adjustment	93,269	11,489	163,215	(21,734)
Pension and other postretirement benefit plans [Abstract]
Amortization of actuarial losses included in net periodic pension cost	1,375	1,414	4,066	4,240
Amortization of prior service cost included in net periodic pension cost	700	1,042	2,104	3,122
Total pension and other postretirement benefit plans	2,075	2,456	6,170	7,362
Changes in fair value of cash flow hedges [Abstract]
Unrealized net losses arising during period	(192)	(282)	(1,989)	(493)
Net (gains) losses reclassified into earnings	(271)	(36)	(329)	131
Total cash flow hedges	(463)	(318)	(2,318)	(362)
Other	272	240	31	1,632
Other comprehensive earnings (loss)	95,153	13,867	167,098	(13,102)
Comprehensive earnings	$ 274,065	$ 143,951	$ 682,315	$ 334,628