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 income	$ 19,991	$ 36,446
Other comprehensive income, before tax:
Foreign currency translations adjustments	1,004	65
Unrealized gains (losses) on available for sale securities
Unrealized holding gains (losses) arising during period	2	(11)
Income tax expense (benefit)	1	(4)
Unrealized gains (losses) on available for sale securities, net of tax	1	(7)
Other comprehensive income, net of tax	1,005	58
Comprehensive income	$ 20,996	$ 36,504

This item represents the tax effects occurring during the period which are related to the net unrealized gain (loss) resulting from changes in the fair [carrying] value during the period of available-for-sale securities. Such tax affects would have been charged or credited directly to other comprehensive income or to related components of shareholders' equity.

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