Comprehensive Income (Schedule of Net Income (Loss) to Comprehensive Income (Loss)) (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	$ 22,796	$ 28,521	$ 59,242	$ 49,802
Unrealized gains on available for sale securities, net	54	26	48	4
Currency translation adjustments, net	886	916	951	(700)
Comprehensive income	$ 23,736	$ 29,463	$ 60,241	$ 49,106

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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+ Details

- Definition

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

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+ 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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+ Details

- Definition

This element represents Other Comprehensive Income or Loss, Net of Tax, for the period. Includes deferred gains or losses on qualifying hedges, unrealized holding gains or losses on available-for-sale securities, minimum pension liability, and cumulative translation adjustment. 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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