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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Furniture, Fixtures and Equipment, net to Reimbursable Expenditures (Details) - USD ($) | 12 Months Ended
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Dec. 31, 2022 | Dec. 31, 2021
Furniture, Fixtures and Equipment, net |  |
Capitalized costs associated with system and website development | $ 1,700,000 | $ 800,000
Goodwill |  |
Impairment of goodwill | 0 | 0
Debt Issuance Costs |  |
Amortization of debt issuance costs | 340,000 | 354,000
Reimbursable Expenditures |  |
Reimbursable expenditures | $ 800,000 | $ 300,000
Furniture Fixtures And Equipment | Minimum |  |
Furniture, Fixtures and Equipment, net |  |
Estimated useful life of assets | 2 years |
Furniture Fixtures And Equipment | Maximum |  |
Furniture, Fixtures and Equipment, net |  |
Estimated useful life of assets | 5 years |
Leasehold Improvements | Minimum |  |
Furniture, Fixtures and Equipment, net |  |
Estimated useful life of assets | 2 years |
Leasehold Improvements | Maximum |  |
Furniture, Fixtures and Equipment, net |  |
Estimated useful life of assets | 5 years |

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