Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Consolidated Statements of Comprehensive Income [Abstract]
Net income	$ 962,542	$ 955,457	$ 1,376,219
Foreign currency forward exchange contracts:
Unrealized holding gain (loss)	(625)	2,334	6,395
Reclassification adjustment for gain included in net income	(6,728)	(1,164)	(4,832)
Investments in marketable securities:
Unrealized holding gain (loss) on investments	(46)	343	41
Reclassification adjustment for (gain) loss included in net income	(384)	23	(509)
Total other comprehensive gain (loss)	(7,783)	1,536	1,095
Comprehensive income	$ 954,759	$ 956,993	$ 1,377,314