Condensed Consolidated Statements Of Income Condensed Consolidated Statements of Income (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Allocated Share-based Compensation Expense	$ 2,770	$ 2,191	$ 8,943	$ 6,538
Cost of Sales [Member]
Allocated Share-based Compensation Expense	99	82	273	263
Selling and Marketing Expense [Member]
Allocated Share-based Compensation Expense	624	443	1,811	1,360
Research and Development Expense [Member]
Allocated Share-based Compensation Expense	227	175	635	537
General and Administrative Expense [Member]
Allocated Share-based Compensation Expense	$ 1,820	$ 1,491	$ 6,224	$ 4,378