Consolidated Statements Of Comprehensive Income (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Statement of Comprehensive Income [Abstract]
Tax (provision)/benefit of marketable securities unrealized gain (loss)	$ 31,468	$ (39,676)	$ 136
Tax (provision)/benefit of foreign currency translation gain (loss)	$ 0	$ (1,827)	$ (1,177)