Revenue Recognition - Disaggregation (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Disaggregation of revenue
Total revenue	$ 32,865	$ 34,038
Deferred Revenue
Revenue recognized	2,000
Product
Disaggregation of revenue
Total revenue	16,382	17,541
Service
Disaggregation of revenue
Total revenue	16,483	16,497
Marketplaces
Disaggregation of revenue
Total revenue	18,741	20,838
Marketplaces \| Product
Disaggregation of revenue
Total revenue	16,381	17,541
Marketplaces \| Service
Disaggregation of revenue
Total revenue	2,360	3,297
Media
Disaggregation of revenue
Total revenue	14,124	13,200
Media \| Product
Disaggregation of revenue
Total revenue	1
Media \| Service
Disaggregation of revenue
Total revenue	$ 14,123	$ 13,200

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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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