The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Goodwill and Intangible Assets (Narrative) (Details) $ in Thousands	3 Months Ended		6 Months Ended	9 Months Ended
	Sep. 30, 2019 USD ($) segment	Sep. 30, 2018 USD ($)	Jun. 30, 2019 USD ($) segment	Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($)	Apr. 01, 2019 USD ($)	Dec. 31, 2018 USD ($)
Finite-Lived Intangible Assets [Line Items]
Number of reportable segments \| segment	1		2
Net carrying value	$ 458			$ 458			$ 304
Amortization expense	140	$ 199		356	$ 599
Cubic Creative, Inc.[Member]
Finite-Lived Intangible Assets [Line Items]
Goodwill						$ 1,593
Goodwill impairment	1,593
Cubic Creative, Inc.[Member] \| Marketing and Event Marketing Services
Finite-Lived Intangible Assets [Line Items]
Goodwill			$ 1,593
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets excluding goodwill	510			$ 510
Customer Relationships [Member] \| Marketing and Event Marketing Services
Finite-Lived Intangible Assets [Line Items]
Definite-lived intangibles, useful life				2 years
Net carrying value	382			$ 382
Developed Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets excluding goodwill	1,520			$ 1,520
Developed Technology [Member] \| Marketing and Event Marketing Services
Finite-Lived Intangible Assets [Line Items]
Definite-lived intangibles, useful life				5 years
Net carrying value that will be fully amortized by end of 2019	$ 76			$ 76