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Summary of Significant Accounting Policies - Summary of Intangible Assets (Details) - USD ($) $ in Thousands | 9 Months Ended |
--- | --- | ---
Sep. 30, 2021 | Dec. 31, 2020
Finite Lived Intangible Assets [Line Items] |  |
Intangible assets, Gross Carrying Amount | $ 740 | $ 972
Intangible assets, Accumulated Amortization | (359) | (445)
Intangible assets, Net Carrying Value | $ 381 | 527
Customer Relationships |  |
Finite Lived Intangible Assets [Line Items] |  |
Intangible assets, Useful Life | 1 year 3 months |
Intangible assets, Gross Carrying Amount |  | 237
Intangible assets, Accumulated Amortization |  | (228)
Intangible assets, Net Carrying Value |  | 9
Acquired Proprietary Software |  |
Finite Lived Intangible Assets [Line Items] |  |
Intangible assets, Useful Life | 5 years |
Intangible assets, Gross Carrying Amount | $ 151 | 150
Intangible assets, Accumulated Amortization | (58) | (35)
Intangible assets, Net Carrying Value | $ 93 | 115
Reacquired Rights |  |
Finite Lived Intangible Assets [Line Items] |  |
Intangible assets, Useful Life | 3 years 10 months 13 days |
Intangible assets, Gross Carrying Amount | $ 505 | 503
Intangible assets, Accumulated Amortization | (250) | (152)
Intangible assets, Net Carrying Value | $ 255 | 351
Internally Developed Software |  |
Finite Lived Intangible Assets [Line Items] |  |
Intangible assets, Useful Life | 3 years |
Intangible assets, Gross Carrying Amount | $ 84 | 82
Intangible assets, Accumulated Amortization | (51) | (30)
Intangible assets, Net Carrying Value | $ 33 | $ 52

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