CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Net income, as reported	$ 286,219	$ 212,029	$ 208,716
Other comprehensive income (loss):
Change in unrealized gain on available-for-sale securities, net of tax	1,478	3,111	4,071
Foreign currency translation adjustments	(3,306)	1,837	2,087
Comprehensive income	$ 284,391	$ 216,977	$ 214,874

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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-Name Accounting Standards Codification

-Glossary Comprehensive Income

-URI http://asc.fasb.org/extlink&oid=6508144

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-Name Accounting Standards Codification

-Glossary Net Income

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-Glossary Other Comprehensive Income

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+ Details

- Definition

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, attributable to the parent entity.

+ References

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+ Details

- Definition

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 (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 (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 (losses) realized upon the sale of securities, after tax; and (3) the unrealized gains (losses) realized upon the write-down of securities, after tax.

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+ Details