Consolidated Statements of Comprehensive Income (Parenthetical) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Statement of Comprehensive Income [Abstract]
Tax (provision)/ benefit of foreign currency translation gain	$ 2,809	$ (1,977)	$ 1,254	$ (238)
Tax (provision)/benefit of marketable securities unrealized gain				$ 136