Other Comprehensive Earnings (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Foreign currency translation adjustments [Abstract]
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, before Tax									$ (86,876)	$ (108,748)	$ (131,420)
Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Tax									(18,827)	(11,646)	(19,523)
Total foreign currency translation adjustments									(105,703)	(120,394)	(150,943)
Pension and other postretirement benefit plans [Abstract]
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, before Tax									5,936	35,727	(70,705)
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Tax									(4,560)	(11,791)	20,994
Pension and other postretirement benefit plans									(1,376)	(23,936)	49,711
Changes in fair value of cash flow hedges [Abstract]
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, before Tax									860	(671)	(375)
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Tax									(301)	235	131
Changes in fair value of cash flow hedges, net of tax									559	(436)	(244)
Other Comprehensive Income Other Adjustment Net Of Tax [Abstract]
Other Comprehensive Income Loss Adjustment Before Tax									(1,119)	1,423	1,067
Other Comprehensive Income Loss Other Adjustment Tax									134	(171)	(128)
Other comprehensive income loss other adjustment, net of tax									(985)	1,252	939
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent [Abstract]
Other Comprehensive Income (Loss), before Tax									(81,199)	(72,269)	(201,433)
Other Comprehensive Income (Loss), Tax									(23,554)	(23,373)	1,474
Other Comprehensive Income (Loss), Net of Tax									(104,753)	(95,642)	(199,959)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax	$ (240,981)				$ (135,278)				(240,981)	(135,278)
Accumulated Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net of Tax	(121,925)				(123,301)				(121,925)	(123,301)
Accumulated Other Comprehensive Income (Loss), Cumulative Changes in Net Gain (Loss) from Cash Flow Hedges, Effect Net of Tax	3,580				4,006				3,580	4,006
Accumulated Other Comprehensive Income (Loss), Net of Tax	(359,326)				(254,573)				(359,326)	(254,573)
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Net earnings	$ 161,162	$ 130,084	$ 118,290	$ 99,356	$ 141,825	$ 186,098	$ 332,396	$ 209,510	508,892	869,829	775,235
Other comprehensive loss									(104,753)	(95,642)	(199,959)
Comprehensive earnings									404,139	774,187	575,276
Other Comprehensive (Income) Loss, Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, Net of Tax [Abstract]
Amortization of actuarial losses									8,544	15,527	8,822
Amortization of prior service costs									6,609	7,541	8,556
Total before tax									15,153	23,068	17,378
Tax expense									(5,073)	(7,768)	(5,969)
Net of tax									10,080	15,300	11,409
Other Comprehensive Income Loss Reclassification Adjustment From AOCI Derivatives Net of Tax [Abstract]
Net losses (gains) reclassified into earnings									638	(166)	(164)
Tax (expense) benefit									(223)	58	57
Net of tax									$ 415	$ (108)	$ (107)