Consolidated Statements Of Comprehensive Income (Parenthetical) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Statement of Other Comprehensive Income [Abstract]
Tax (provision)/benefit of unrealized derivatives gain (loss)	$ (6)	$ (53)	$ 52
Tax (provision)/benefit of foreign currency translation gain (loss)	(1,426)	626	219
Tax (provision)/benefit of marketable securities unrealized gain (loss)	$ (570)	$ (266)	$ 700