Other Comprehensive Earnings (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Foreign currency translation adjustments [Abstract]
Foreign currency translation adjustments, before tax	$ (14,860)	$ 72,823	$ (24,794)	$ 119,725
Foreign currency translation adjustments, tax	1,293	20,446	(1,624)	43,490
Total foreign currency translation adjustment	(13,567)	93,269	(26,418)	163,215
Pension and other postretirement benefit plans [Abstract]
Pension and other postretirement benefit plans, before tax	1,407	3,049	7,765	9,071
Pension and other postretirement benefit plans, tax	(301)	(974)	(1,657)	(2,901)
Total pension and other postretirement benefit plans	1,106	2,075	6,108	6,170
Changes in fair value of cash flow hedges [Abstract]
Changes in fair value of cash flow hedges, before tax	(1,374)	(712)	2,116	(3,566)
Changes in fair value of cash flow hedges, tax	289	249	(444)	1,248
Total cash flow hedges	(1,085)	(463)	1,672	(2,318)
Other comprehensive earnings other adjustment, net of tax [Abstract]
Other, before tax	0	309	0	35
Other, tax	0	(37)	0	(4)
Other comprehensive income loss other adjustment, net of tax	0	272	0	31
Total other comprehensive earnings [Abstract]
Other comprehensive earnings (loss), before Tax	(14,827)	75,469	(14,913)	125,265
Other comprehensive earnings (loss), tax	1,281	19,684	(3,725)	41,833
Other comprehensive (loss) earnings	(13,546)	95,153	(18,638)	167,098
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Net earnings	157,305	178,912	428,698	515,217
Other comprehensive earnings (loss)	(13,546)	95,153	(18,638)	167,098
Comprehensive earnings	143,759	274,065	410,060	682,315
Other Comprehensive Income Loss Reclassification Adjustment from AOCI Foreign Currency Translation Net of Tax [Abstract]
Reclassification of foreign currency translation losses to earnings upon sale of subsidiary	0	0	0	(3,875)
Tax benefit	0	0	0	0
Net of tax	0	0	0	3,875
Other Comprehensive Income Loss Reclassification Adjustment From AOCI Pension And Other Postretirement Benefit Plans Net Of Tax Abstract [Abstract]
Amortization of actuarial losses	517	1,951	4,354	5,771
Amortization of prior service costs	890	1,098	3,411	3,300
Total before tax	1,407	3,049	7,765	9,071
Tax (benefit) provision	(301)	(974)	(1,657)	(2,901)
Net of tax	1,106	2,075	6,108	6,170
Other Comprehensive Income Loss Reclassification Adjustment From AOCI Derivatives Net of Tax [Abstract]
Net (gains) losses reclassified into earnings	460	(417)	(439)	(506)
Tax expense (benefit)	(96)	146	92	177
Net of tax	$ 364	$ (271)	$ (347)	$ (329)