Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
COMPREHENSIVE INCOME:
Net income	$ 252,195	$ 209,942	$ 149,922
Foreign currency translation adjustments, net of tax	(5,708)	2,892	(6,233)
Total comprehensive income	$ 246,487	$ 212,834	$ 143,689