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) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Nov. 30, 2015
Business Acquisition [Line Items]
Goodwill	$ 491	$ 470	$ 471
Amortization of intangibles	3,008	3,096
In-process research and development (IPR&D)
Business Acquisition [Line Items]
Intangible asset impairment		1,200
Product Acquisition Costs
Business Acquisition [Line Items]
Amortization of intangibles	$ 0
Intangible asset impairment		$ 700
Alveda Acquisition
Business Acquisition [Line Items]
Goodwill				$ 400