Goodwill and Intangible Assets (Schedule of Identifiable Intangible Assets) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Jun. 30, 2019
Goodwill And Intangible Assets [Line Items]
Goodwill		$ 1,593
Intangible Assets
Net Carrying Value	$ 304	598
Operating Segments [Member] | Marketing Services [Member]
Goodwill And Intangible Assets [Line Items]
Goodwill		1,593
Intangible Assets
Cost	6,470	2,030
Accumulated Amortization	(3,196)	(1,432)
Asset Impairments	(2,970)
Net Carrying Value	$ 304	$ 598