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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 45
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Topic 230
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Intangible Assets - Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 7,809		$ 7,809		$ 7,808
Accumulated Amortization	(5,755)		(5,755)		(4,703)
Net Carrying Value	2,054		2,054		3,105
Amortization expense	400	$ 400	1,100	$ 1,100
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	790		790		790
Accumulated Amortization	(510)		(510)		(392)
Net Carrying Value	280		280		398
Technology
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	4,811		4,811		4,811
Accumulated Amortization	(3,671)		(3,671)		(3,070)
Net Carrying Value	1,140		1,140		1,741
Trademarks
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	930		930		930
Accumulated Amortization	(508)		(508)		(416)
Net Carrying Value	422		422		514
Partner relationships
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	680		680		680
Accumulated Amortization	(567)		(567)		(397)
Net Carrying Value	113		113		283
Non-compete agreements
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	40		40		40
Accumulated Amortization	(33)		(33)		(23)
Net Carrying Value	7		7		17
Domain names
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	273		273		273
Accumulated Amortization	(273)		(273)		(241)
Net Carrying Value	0		0		32
Patents
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	285		285		284
Accumulated Amortization	(193)		(193)		(164)
Net Carrying Value	$ 92		$ 92		$ 120