Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Statement of Comprehensive Income [Abstract]
Net earnings	$ 133,314	$ 119,350	$ 375,759	$ 349,407
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments (net of tax of $0 in 2014 and 2013)	(11,516)	3,668	(10,967)	(3,692)
Change in marketable securities (net of tax of $0 in 2014 and 2013)	(256)	4	(254)	88
Comprehensive income	$ 121,542	$ 123,022	$ 364,538	$ 345,803

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.

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