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LEASES, Operating Lease Right-of-use Assets and Liabilities (Details) - USD ($) $ in Thousands | 6 Months Ended |
--- | --- | ---
Jun. 30, 2023 | Jun. 30, 2022 | Dec. 31, 2022
Operating Lease, ROU Assets [Abstract] |  |  |
Operating lease ROU assets, Beginning | $ 1,030 |  |
Recognition of ROU asset for Somerville Sublease | 34,410 |  |
Amortization of operating lease ROU assets | (83) | $ (186) |
Operating lease ROU assets, Ending | 35,357 |  |
Operating Lease, Liabilities [Abstract] |  |  |
Operating lease liabilities, Beginning | 1,182 |  |
Recognition of lease liability for Somerville Sublease | 34,169 |  |
Principal payments on operating lease liabilities | (215) |  |
Operating lease liabilities, Ending | 35,136 |  |
Less non-current portion | 34,963 |  | $ 887
Current portion | $ 173 |  |

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- Definition The fair value of initial measurement of operating lease liabilities in noncash financing activities. + References No definition available. + Details
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- Definition The fair value of initial measurement of operating lease ROU assets. + References No definition available. + Details
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- Definition Principal payments on operating lease liabilities. + References No definition available. + Details
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- Definition Present value of lessee's discounted obligation for lease payments from operating lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479041/842-20-45-1 + Details
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- Definition Present value of lessee's discounted obligation for lease payments from operating lease, classified as current. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479041/842-20-45-1 + Details
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- Definition Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479041/842-20-45-1 + Details
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- Definition Amount of lessee's right to use underlying asset under operating lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479041/842-20-45-1 + Details
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- Definition Amount of periodic reduction over lease term of carrying amount of right-of-use asset from operating lease. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 230 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 28 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482740/230-10-45-28 + Details
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