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LIQUIDITY AND CAPITAL RESOURCES (Details) $ in Thousands		1 Months Ended			3 Months Ended		12 Months Ended
	Jan. 11, 2024 USD ($)	Jan. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Jul. 31, 2023 USD ($)	Mar. 31, 2024 USD ($) shares	Mar. 31, 2023 USD ($)	Dec. 31, 2023 USD ($) shares	Apr. 30, 2023 USD ($)	Oct. 31, 2022 USD ($) ft²
Liquidity and Capital Resources [Abstract]
Cash			$ 7,575		$ 5,116		$ 7,575
Accumulated deficit			(186,981)		(193,628)		$ (186,981)
Net loss					(6,647)	$ (5,416)
Net cash used in operating activities					(3,747)	(6,049)
New Facility Lease [Abstract]
Area of premises | ft²									45,500
Letter of credit									$ 4,100
Restricted cash									$ 4,100
Private Placement Offerings [Abstract]
Proceeds received from the convertible notes financing	$ 1,405				$ 1,405	$ 0
Convertible Notes [Member]
Private Placement Offerings [Abstract]
Proceeds received from the convertible notes financing		$ 1,400	$ 16,500	$ 16,500
Lincoln Park [Member]
New Facility Lease [Abstract]
Common stock shares issued and sold (in shares) | shares					0		214,000
Gross proceeds from sale of equity							$ 300
Lincoln Park [Member] | Maximum [Member]
New Facility Lease [Abstract]
Aggregate gross purchase price								$ 10,000

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