Condensed Consolidated Statements Of Income Condensed Consolidated Statements of Income (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Allocated Share-based Compensation Expense	$ 3,168	$ 1,963	$ 6,173	$ 4,347
Cost of Sales [Member]
Allocated Share-based Compensation Expense	91	27	174	181
Selling and Marketing Expense [Member]
Allocated Share-based Compensation Expense	603	426	1,187	917
Research and Development Expense [Member]
Allocated Share-based Compensation Expense	213	222	408	362
General and Administrative Expense [Member]
Allocated Share-based Compensation Expense	$ 2,261	$ 1,288	$ 4,404	$ 2,887