Comprehensive Income (Details) (USD $) In Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Comprehensive Income
Net income	$ 179,115	$ 181,706	$ 247,431	$ 214,309
Foreign currency translation adjustments	9,384	(21,173)	26,889	(14,687)
Amortization of net prior service costs and net actuarial losses, net of taxes	3,435	3,841	6,684	7,492
Adjustments of marketable equity securities, net of taxes	(427)	333	(408)	665
Comprehensive income	191,507	164,707	280,596	207,779
Comprehensive Income (Textuals) [Abstract]
Tax effect of amortization of net prior service costs and net actuarial losses	(2,873)	(1,210)	(5,961)	(3,624)
Tax effect of adjustments of marketable equity securities	$ 273	$ (213)	$ 261	$ (425)

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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Reference 6: http://www.xbrl.org/2003/role/presentationRef
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Reference 7: http://www.xbrl.org/2003/role/presentationRef
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+ Details

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

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+ Details

- 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.

+ References

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+ Details

- Definition

The increase (decrease) in accumulated comprehensive income during the period related to pension and other postretirement benefit plans, after tax. While for technical reasons this element has no balance attribute, the default assumption is a credit balance consistent with its label.

+ References+ Details

- Definition

Tax effects of the increase (decrease) to accumulated comprehensive income during the period related to benefit plans. While for technical reasons this element has no balance attribute, the default assumption is a credit balance consistent with its label.

+ References+ Details

- 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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