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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details) | 1 Months Ended | 3 Months Ended | 6 Months Ended | 9 Months Ended | 12 Months Ended |  |
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Jan. 31, 2022 USD ($) | Dec. 31, 2021 USD ($) | Sep. 30, 2016 USD ($) | Jun. 30, 2022 USD ($) | Dec. 31, 2021 USD ($) | Jun. 30, 2021 USD ($) | Jun. 30, 2022 USD ($) | Jun. 30, 2021 USD ($) | Sep. 30, 2021 USD ($) | Dec. 31, 2021 USD ($) item | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($) | Mar. 31, 2021 | Jan. 01, 2019 USD ($)
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Insurance coverage limit |  | $ 250,000 |  |  | $ 250,000 |  |  |  |  | $ 250,000 |  |  |  |
Intangibles impairment charge |  |  |  | $ 27,764,000 |  | $ 0 | $ 27,764,000 | $ 0 | $ 31,700,000 | $ 31,700,000 | $ 0 | $ 0 |  |
Impairment of intangible assets |  |  |  |  |  |  |  |  |  |  | 0 |  |  |
Number of reporting units | item |  |  |  |  |  |  |  |  |  | 1 |  |  |  |
Goodwill |  | $ 13,064,000 |  | $ 0 | $ 13,064,000 |  | 0 |  | $ 13,100,000 | $ 13,064,000 | 13,064,000 |  |  |
Goodwill impairment |  |  |  |  |  |  | $ 13,064,000 |  |  | $ 0 | $ 0 |  |  |
License agreement, royalty rate |  | 2.00% |  | 2.00% | 2.00% |  | 2.00% |  |  | 2.00% |  |  |  |
Index rate, high-yield |  | 0.080 |  |  | 0.080 | 0.066 |  | 0.066 | 0.075 | 0.080 | 0.084 |  | 0.074 |
Right-of-use asset |  | $ 123,300 |  | $ 41,700 | $ 123,300 |  | $ 41,700 |  |  | $ 123,300 |  |  |  |
Lease liability |  | $ 124,000 |  |  | $ 124,000 |  |  |  |  | $ 124,000 |  |  |  |
Dividend yield |  |  |  |  |  |  |  |  |  | 0.00% |  |  |  |
License and related revenue |  |  |  | $ 0 |  | $ 2,234,000 | $ 0 | $ 6,544,000 |  | $ 26,544,000 | $ 11,236,000 | $ 0 |  |
Discount Rate |  |  |  |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Weighted-average cost of capital |  | 9.30% |  |  | 9.30% | 6.80% |  | 6.80% | 8.60% | 9.30% | 8.80% |  | 7.80% |
Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Probability of achieving clinical and regulatory milestones |  | 45.00% |  |  | 45.00% |  |  |  |  | 45.00% |  |  |  |
Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Probability of achieving clinical and regulatory milestones |  | 55.00% |  |  | 55.00% |  |  |  |  | 55.00% |  |  |  |
Cumulative Effect, Period of Adoption, Adjustment |  |  |  |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Right-of-use asset |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 200,000
Lease liability |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 200,000
Roche | Subsequent Event |  |  |  |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from milestone achieved | $ 20,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Performance-Based Awards |  |  |  |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Award vesting period |  |  |  |  |  |  |  |  |  | 4 years |  |  |  |
Expected term |  |  |  |  |  |  |  |  |  | 10 years |  |  |  |
Licensing Agreements | Roche |  |  |  |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Milestone payment |  | $ 20,000,000 |  |  |  |  |  |  |  |  |  |  |  |
Milestone payment term |  | 30 days |  |  |  |  |  |  |  |  |  |  |  |
Vicinium | United States | IPR&D intangible assets: |  |  |  |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Intangibles impairment charge |  |  |  |  |  |  |  |  |  | $ 31,700,000 |  |  |  |
EBI-031 | Roche |  |  |  |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
License and related revenue |  |  | $ 20,000,000 |  | $ 20,000,000 |  |  |  |  |  |  |  |  |
Proceeds from milestone achieved | 20,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |
EBI-031 | Roche | Subsequent Event |  |  |  |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from milestone achieved | $ 20,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |
EBI-031 | Roche | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
License agreement, royalty rate |  | 7.50% |  | 7.50% | 7.50% |  | 7.50% |  |  | 7.50% |  |  |  |
EBI-031 | Roche | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
License agreement, royalty rate |  | 15.00% |  | 15.00% | 15.00% |  | 15.00% |  |  | 15.00% |  |  |  |
Lab equipment |  |  |  |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Estimated useful life |  |  |  |  |  |  |  |  |  | 5 years |  |  |  |
Furniture and fixtures |  |  |  |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Estimated useful life |  |  |  |  |  |  |  |  |  | 4 years |  |  |  |
Computer equipment |  |  |  |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Estimated useful life |  |  |  |  |  |  |  |  |  | 3 years |  |  |  |
Leasehold improvements |  |  |  |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Estimated useful life |  |  |  |  |  |  |  |  |  | 5 years |  |  |  |

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