Fair Value Of Financial Instruments (Tables)	9 Months Ended
Sep. 30, 2021
Fair Value Of Financial Instruments [Abstract]
Summary Of Assets Measured At Fair Value On Nonrecurring Basis	Carrying Value September 30, Level2021 2020Leasehold improvements, property and equipment, net3$ 544 $ 3,427Operating lease assets3 2,857 7,113Total $ 3,401 $ 10,540

Tabular disclosure of assets and liabilities by class, including financial instruments measured at fair value that are classified in shareholders' equity, if any, that are measured at fair value on a nonrecurring basis in periods after initial recognition (for example, impaired assets). Disclosures may include, but are not limited to: (a) the fair value measurements recorded and the reasons for the measurements and (b) the level within the fair value hierarchy in which the fair value measurements are categorized in their entirety (levels 1, 2, 3).

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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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