Condensed Consolidated Statements Of Comprehensive Income (USD $) In Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Dec. 31, 2010
Condensed Consolidated Statements Of Comprehensive Income
Net income	$ 14,701	$ 20,137	$ 29,214	$ 38,279
Other comprehensive income (loss):
Foreign currency translation adjustments	1,253	(5,069)	5,837	(8,023)
Unrealized gain on investments, net of tax	525	425	754	248
Other	20	11	33	1
Comprehensive income	16,499	15,504	35,838	30,505
Foreign currency translation adjustments	3,066		3,066		(2,771)
Unrealized loss on investments, net of tax	(3,099)		(3,099)		(3,853)
Other	(305)		(305)		(338)
Accumulated other comprehensive loss	$ (338)		$ (338)		$ (6,962)

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Others Component Of Accumulated Other Comprehensive Losses

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Accumulated appreciation or loss, net of tax, in value of the total of unsold securities at the end of an accounting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 130
-Paragraph 26

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Accumulated adjustment, net of tax, that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency from the functional currency of the reporting entity, net of reclassification of realized foreign currency translation gains (losses).

+ References

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-Name Statement of Financial Accounting Standard (FAS)
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-Name Accounting Principles Board Opinion (APB)
-Number 12
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-Paragraph 17, 18, 19, 22, 23, 24, 25, 26

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-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 45

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at fiscal year-end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, and unrealized gains and losses on certain investments in debt and equity securities as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Article 3

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-Name Regulation S-X (SX)
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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.

+ References

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The portion of consolidated profit or loss for the period, net of income taxes, which is attributable to the parent. If the entity does not present consolidated financial statements, the amount of profit or loss for the period, net of income taxes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
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Adjustment that results from the process of translating subsidiary financial statements and foreign equity investments into functional currency of the reporting entity, net of tax.

+ References

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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 52
-Paragraph 13, 20, 31

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Appreciation or loss in value (before reclassification adjustment) of the total of unsold securities during the period being reported on, net of tax. Reclassification adjustments include: (1) the unrealized holding gain or loss, net of tax, at the date of the transfer for a debt security from the held-to-maturity category transferred into the available-for-sale category. Also includes the unrealized gain or loss at the date of transfer for a debt security from the available-for-sale category transferred into the held-to-maturity category; (2) the unrealized gains or losses realized upon the sale of securities, after tax; and (3) the unrealized gains or losses realized upon the write-down of securities, after tax.

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