STOCKHOLDERS' EQUITY - 2018 INDUCEMENT AWARD PLAN (Details) - 2018 Inducement Award Plan - shares	1 Months Ended
Feb. 28, 2022	May 31, 2021	Feb. 28, 2021	Feb. 29, 2020	Jan. 31, 2019	Dec. 31, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, shares reserved for future issuance (in shares)	16,100,000
Common stock, increase in option reserves (in shares)	1,000,000	5,000,000	800,000	1,300,000	5,000,000	3,000,000

Aggregate number of common shares reserved for future issuance.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

The addition or reduction in the number of reserved shares that could potentially be issued under the option plan attributable to reasons other than grants, exercises, forfeitures, and expirations during the reporting period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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