BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES - Deferred Revenues (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020	Dec. 31, 2019
Deferred revenue, net of current portion	$ 5,073	$ 5,398
Contract with Customer, Liability, Total	6,795	6,770
Sports Wagering Agreements
Contract with Customer, Liability, Total			$ 6,000
Other accrued liabilities
Deferred revenue, current	$ 1,722	$ 1,372

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as noncurrent.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=121556615&loc=SL49130532-203044

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121556615&loc=SL49130531-203044

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130549-203045

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant