Financial Instruments And Concentration Of Credit Risk (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Concentration Risk [Line Items]
Interest rate swap notional amount	$ 163,900	$ 172,500
Fixed interest rate	1.4935%
Fair value of interest rate swap	$ 500	0
Unrealized gain on interest rate swap	(500)
Unrealized gain on interest rate swap, net of tax	$ 286	$ 0	$ 0
Accounts Receivable [Member]
Concentration Risk [Line Items]
Concentration Risk Customer Accounts Receivable	The Company had two customers whose gross accounts receivable exceeded 10% of total gross accounts receivable as of December 31, 2016. One customer represented 15% of our total gross accounts receivable and the second customer represented 11%.
Accounts Receivable [Member] | Largest Accounts Receivable Customer [Member]
Concentration Risk [Line Items]
Concentration risk, percentage	15.00%
Accounts Receivable [Member] | Second Largest Accounts Receivable Customer [Member]
Concentration Risk [Line Items]
Concentration risk, percentage	11.00%