Consolidated Statements Of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2012	Mar. 31, 2011
Consolidated Statements Of Comprehensive Income [Abstract]
Net earnings	$ 100,194	$ 79,547
Other comprehensive income, net of tax:
Foreign currency translation adjustments	1,829	1,319
Change in marketable securities	14	88
Other comprehensive income	1,843	1,407
Comprehensive income	$ 102,037	$ 80,954

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

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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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- Definition

Gross appreciation or the gross loss in value of the total unsold securities. While for technical reasons this element has no balance attribute, the default assumption is a credit balance consistent with its label.

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- Definition

Adjustment that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency of the reporting entity, net of tax.

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