Revenue Recognition - Disaggregation (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Disaggregation of revenue
Total revenue	$ 154,956	$ 155,042
Deferred Revenue
Revenue recognized	1,800
Product
Disaggregation of revenue
Total revenue	75,795	83,458
Service
Disaggregation of revenue
Total revenue	79,161	71,584
Marketplaces
Disaggregation of revenue
Total revenue	89,625	93,937
Marketplaces \| Product
Disaggregation of revenue
Total revenue	75,787	83,458
Marketplaces \| Service
Disaggregation of revenue
Total revenue	13,838	10,479
Media
Disaggregation of revenue
Total revenue	65,331	61,105
Media \| Product
Disaggregation of revenue
Total revenue	8
Media \| Service
Disaggregation of revenue
Total revenue	$ 65,323	$ 61,105

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Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130549-203045

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+ References

No definition available.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

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