Significant Accounting Policies (Deferred Financing Costs) (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Aug. 03, 2018	Mar. 09, 2018
Amortization of deferred financing costs		$ 300	$ 300	$ 200
Write-off of deferred financing costs				$ 768
Unamortized debt issuance expense		1,600	700
Deferred financing costs		$ 1,603	$ 749
Prior Credit Facility [Member]
Write-off of deferred financing costs	$ 800
First Amended and Restated Revolving Credit, Term Loan and Security Agreement [Member]
Deferred financing costs					$ 400
New Markets Tax Credit (NMTC) Program [Member]
Deferred financing costs						$ 700