Summary of Significant Accounting Policies - Narrative (Details) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021 USD ($) shares	Jun. 30, 2021 USD ($) segment shares
Finite-Lived Intangible Assets [Line Items]
Research and development expense	$ 2,410	$ 2,739
Number of reportable segments \| segment		1
Dilutive potential common shares \| shares	0	0
Capitalized development costs	$ 200
Noncancellable service contract period		5 years
IP license intangible
Finite-Lived Intangible Assets [Line Items]
Useful life of intangible assets		2 years
Favorable lease intangible
Finite-Lived Intangible Assets [Line Items]
Useful life of intangible assets		30 years
Computer software and website development costs
Finite-Lived Intangible Assets [Line Items]
Useful life of intangible assets		3 years

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Additions made to capitalized computer software costs during the period.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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The sum of dilutive potential common shares or units used in the calculation of the diluted per-share or per-unit computation.

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