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Critical and Significan Accounting Policies (Details 1) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Jan. 01, 2018
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Accounts Receivable, Net, Current	$ 50,075	$ 49,311
Inventory, Net	72,904	68,683
Retained earnings	347,046	353,685
Accounting Standards Update 2014-09 [Member] \| Proforma adjustment
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Accounts Receivable, Net, Current			$ 781
Inventory, Net			(660)
Retained earnings			121
Accounting Standards Update 2014-09 [Member] \| Scenario forecast
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Accounts Receivable, Net, Current			50,856
Inventory, Net			72,244
Retained earnings			$ 347,167
Accounting Standards Update 2017-07 [Member] \| Proforma adjustment
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
New Accounting Pronouncement Or Change In Accounting Principle Effect Of Adoption Quantification	$ 6,400	$ 4,100