Condensed Consolidated Statements of Comprehensive Income (unaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Condensed Consolidated Statements of Comprehensive Income (unaudited) [Abstract]
Net earnings	$ 151,416	$ 155,773
Other comprehensive income/(loss), net of tax:
Foreign currency translation adjustments	1,743	(92,010)
Post retirement benefit plan adjustment	0	(1,063)
Total other comprehensive income/(loss), net of tax	1,743	(93,073)
Comprehensive income	$ 153,159	$ 62,700

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Other Comprehensive Income
-URI http://asc.fasb.org/extlink&oid=51831270

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-URI http://asc.fasb.org/extlink&oid=51831223

Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Amount before tax, after reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

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