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OPERATING LEASES (Details) - USD ($) | Mar. 10, 2020 | Sep. 10, 2019 | Dec. 31, 2020 | Mar. 31, 2020 | Dec. 31, 2019 | Oct. 31, 2019 | Oct. 01, 2019 | Apr. 30, 2019
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Lessee Lease Description [Line Items] |  |  |  |  |  |  |  |
Operating Lease, Right-of-Use Asset |  |  | $ 5,295,000 |  | $ 2,497,000 |  |  |
Operating Lease, Liability |  |  | $ 5,677,000 |  |  |  |  |
Menlo Park Office Space Lease |  |  |  |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |  |  |  |
Operating lease term, additional period extension |  | 2 months |  |  |  |  |  |
Operating Lease, Percentage of Discount Rate |  |  |  | 5.00% |  |  |  |
Operating Lease, Right-of-Use Asset |  |  |  | $ 149,000 |  |  |  |
Operating Lease, Liability |  |  |  | $ 149,000 |  |  |  |
New Jersey Office Space Lease |  |  |  |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |  |  |  |
Operating Lease, Percentage of Discount Rate |  |  |  |  |  |  | 8.00% |
Operating Lease, Right-of-Use Asset |  |  |  |  |  |  | $ 2,356,000 |
Operating Lease, Liability |  |  |  |  |  |  | $ 2,356,000 |
Operating lease, initial term |  |  |  |  |  |  |  | 11 years
Operating lease term, option to extend additional period |  |  |  |  |  |  |  | 5 years
Operating lease,remaining lease term |  |  | 9 years 9 months 18 days |  |  |  |  |
Foster City Office Space Lease |  |  |  |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |  |  |  |
Operating Lease, Percentage of Discount Rate | 7.00% |  |  |  |  |  |  |
Operating Lease, Right-of-Use Asset | $ 3,426,000 |  |  |  |  |  |  |
Operating Lease, Liability | $ 3,426,000 |  |  |  |  |  |  |
Operating lease, initial term | 87 months |  |  |  |  | 87 months |  |
Operating lease term, option to extend additional period |  |  |  |  |  | 5 years |  |
Operating lease,remaining lease term |  |  | 6 years 6 months |  |  |  |  |
Operating lease, rent abatement period | 3 months |  |  |  |  |  |  |

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- Definition Operating lease term additional period extension. + References No definition available. + Details
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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. + Details
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- Definition Discount rate used by lessee to determine present value of operating lease payments. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918673-209980 + Details
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- Definition Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918673-209980 + Details
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- Definition Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918673-209980 + Details
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- Definition Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 55 -Paragraph 53 -URI http://asc.fasb.org/extlink&oid=121568110&loc=SL77918982-209971 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (g)(3) -URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918686-209980 + Details
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