Goodwill and Intangible Assets (Schedule of Identifiable Intangible Assets) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2019	Dec. 31, 2018
Goodwill And Intangible Assets [Line Items]
Goodwill
Intangible Assets
Net Carrying Value	228	$ 304
Operating Segments [Member] \| Marketing Services [Member]
Goodwill And Intangible Assets [Line Items]
Goodwill
Intangible Assets
Cost	1,520	6,470
Accumulated Amortization	(1,292)	(3,196)
Asset Impairments		(2,970)
Net Carrying Value	$ 228	$ 304

Goodwill And Intangible Assets [Line Items]

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- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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