STOCK-BASED COMPENSATION, RSUs (Details) $ / shares in Units, $ in Millions	3 Months Ended
Mar. 31, 2022 USD ($) Goals $ / shares shares	Mar. 31, 2021 shares
RSU [Member]
Outstanding Restricted Stock Units [Roll Forward]
Outstanding, Beginning balance (in shares)	240,000
Granted (in shares)	1,101,000	0
Released (in shares)	(9,000)
Cancelled (in shares)	(9,000)
Outstanding, Ending balance (in shares)	1,323,000	0
Balance expected to vest (in shares)	772,000
Weighted Average Fair Value Per Share [Abstract]
Weighted Average Fair Value Per Share, Beginning balance (in dollars per share) \| $ / shares	$ 13.80
Granted (in dollars per share) \| $ / shares	1.93
Released (in dollars per share) \| $ / shares	4.21
Cancelled (in dollars per share) \| $ / shares	4.21
Weighted Average Fair Value Per Share, Ending balance (in dollars per share) \| $ / shares	$ 4.05
Number of stock units awards outstanding (in shares)	1,323,000	0
Unamortized stock-based compensation expense \| $	$ 3.6
Weighted average remaining requisite service period	2 years 7 months 2 days
2022 PSUs [Member]
Weighted Average Fair Value Per Share [Abstract]
Number of performance goals are subject to achieve \| Goals	4
Restricted stock units vesting period	3 years
2022 PSUs [Member] \| Employees [Member]
Outstanding Restricted Stock Units [Roll Forward]
Granted (in shares)	1,101,000
2022 PSUs [Member] \| Dr. Federoff [Member]
Outstanding Restricted Stock Units [Roll Forward]
Granted (in shares)	414,000

The number of performance goals are subject to achieve under 2022 performance based restricted stock units.

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options expected to vest.

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No definition available.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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