Summary of Significant Accounting Policies - Narrative (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021 USD ($) shares	Sep. 30, 2021 segment shares
Finite-Lived Intangible Assets [Line Items]
Number of reportable segments \| segment		1
Dilutive potential common shares (in shares) \| shares	0	0
Capitalized development costs \| $	$ 200
Noncancellable service contract period		5 years
Restricted Stock Units (RSUs)
Finite-Lived Intangible Assets [Line Items]
Vesting period of award		3 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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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
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