DESCRIPTION OF BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Concentrations (Details) $ in Millions	12 Months Ended
Dec. 31, 2020 USD ($) item customer	Dec. 31, 2019 customer item	Dec. 31, 2018 item
Revenue \| Customer concentration
Number of major customers \| customer	3	3
Revenue \| Customer concentration \| Customer One [Member]
Concentration Risk, Percentage	31.00%	32.00%	33.00%
Revenue \| Customer concentration \| Customer Two [Member]
Concentration Risk, Percentage	24.00%	25.00%	23.00%
Revenue \| Customer concentration \| Customer Three [Member]
Concentration Risk, Percentage	19.00%	23.00%	21.00%
Accounts receivable \| Customer concentration
Concentration Risk, Percentage	81.00%
Cost of goods sold \| Supplier concentration \| One supplier
Concentration Risk, Percentage	10.00%	13.00%	13.00%
Number of major suppliers \| item	1	1	1
Amount payable to supplier \| $	$ 0.9

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 42
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e9054-108599

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6351-108592

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13531-108611

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13537-108611

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration