Revenue Recognition (Impact of New Revenue Guidance on Balance Sheet) (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Jan. 01, 2018	Dec. 31, 2017
Assets
Accounts Receivable	$ 95,038		$ 79,120
Inventory	84,633		71,524
Liabilities
Deferred tax liability	42,854		39,269
Stockholders' Equity:
Retained Earnings	123,208		$ 115,737
Accounting Standards Update (“ASU”) No. 2014-09 | Balances without adoption of Topic 606
Assets
Accounts Receivable	92,910
Inventory	86,339
Liabilities
Deferred tax liability	42,744
Stockholders' Equity:
Retained Earnings	122,830
Accounting Standards Update (“ASU”) No. 2014-09 | Effect of Change Higher/(Lower)
Assets
Accounts Receivable	2,128
Inventory	(1,706)
Liabilities
Deferred tax liability	110
Stockholders' Equity:
Retained Earnings	$ 378	$ 378