Summary of Significant Accounting Policies (Details Textuals) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Deferred Tax Assets, Net of Valuation Allowance, Current	$ 71,629		$ 71,629		$ 67,483
Deferred Tax Liabilities, Net, Current	22,920		22,920		$ 22,435
Summary of Significant Accounting Policies (Textuals) [Abstract]
Amortization expense	2,200	$ 1,500	5,800	$ 4,700
Future Amortization Expense Current Year			8,200
Aggregate amortization expense for 2016	9,800		9,800
Aggregate amortization expense for 2017	9,400		9,400
Aggregate amortization expense for 2018	9,000		9,000
Aggregate amortization expense for 2019	8,700		8,700
Aggregate amortization expense for 2020	8,100		8,100
Purchased Intangible Amortization, Gross	2,000	1,300	5,200	4,200
Purchased intangible amortization, net of tax	1,300	900	3,500	2,900
Amortization expense associated with capitalized software	6,800	6,200	$ 20,200	18,100
Standard Warranty Period			one
Share - based compensation expense	$ 3,600	$ 3,400	$ 10,900	$ 10,300