Fair Value Of Financial Instruments	12 Months Ended
Dec. 31, 2021
Fair Value Of Financial Instruments [Abstract]
Fair Value Of Financial Instruments	4. Fair Value of Financial InstrumentsAssets and Liabilities Measured at Fair Value on a Recurring Basis The carrying value of our cash and cash equivalents, restricted cash, accounts receivable and accounts payable approximate fair value because of their short-term nature.Our investments are comprised of U.S. Treasury securities, a corporate debt security, non-marketable equity securities, and an equity method investment. We also maintain a deferred compensation plan with related assets held in a rabbi trust. We designate the appropriate classification of our investments at the time of purchase based upon the intended holding period.Held-to-Maturity InvestmentsU.S. Treasury Securities As of December 31, 2021, we held $501,288 of U.S. Treasury securities with maturities of up to 24 months, of which $260,945 mature within one year. As of December 31, 2020, we held $445,944 of U.S. Treasury securities with maturities of up to 16 months, of which $343,616 matured within one year. Our investments in U.S. Treasury securities are held at amortized cost. The fair value of our held-to-maturity U.S. Treasury security investments is measured using Level 1 inputs (quoted prices for identical assets in active markets). For the years ended December 31, 2021 and 2020, the fair value of our securities were $500,172 and $445,828, respectively. We recognize a reserve for expected credit losses when lifetime credit losses are expected by management. As of December 31, 2021, management has concluded there is no risk of non-payment with respect to our U.S. Treasury security investments. Corporate Debt SecurityOn September 30, 2021, we acquired a promissory note issued by a supplier in exchange for $18,000. The promissory note has a principal balance of $18,000 and bears interest at a rate equal to the 3-month U.S. dollar London Interbank Offered Rate (“LIBOR”) plus a fixed interest spread. Accrued interest is paid quarterly in arrears and principal is payable in accordance with an amortization schedule beginning on December 31, 2022. The promissory note matures on September 30, 2028. Our investment in the corporate debt security is held at amortized cost and approximates fair value as of December 31, 2021. As of December 31, 2021, we maintained a reserve of $423 for expected credit losses associated with the investment.Rabbi TrustWe have elected to fund certain deferred compensation obligations through a rabbi trust, the assets of which are designated as trading securities, as described further in Note 9. “Employee Benefit Plans.”Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis Assets recognized or disclosed at fair value on the consolidated financial statements on a nonrecurring basis include items such as leasehold improvements, property and equipment, certain long-term investments, operating lease assets, other assets, and goodwill. These assets are measured at fair value whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. The following table summarizes our assets measured at fair value by hierarchy level on a nonrecurring basis: Carrying Value December 31, Level2021 2020Leasehold improvements, property and equipment, net3$ 1,041 $ 4,682Operating lease assets3 2,791 10,372Total $ 3,832 $ 15,054Fair value of these assets was measured using Level 3 inputs (unobservable inputs for the asset or liability). Unobservable inputs include the discount rate, projected restaurant revenues and expenses, and sublease income if we are closing the restaurant. For the years ended December 31, 2021, 2020 and 2019 we recorded asset impairments related to restaurants and offices of $4,727, $16,683 and $2,897, respectively. Carrying value after the impairment charges approximates fair value.Non-Marketable Equity SecuritiesOn March 23, 2021, we acquired 766 shares of the Series C Preferred Stock of Nuro, Inc. (“Nuro”) in exchange for cash consideration of $10,000. Our investment represents a minority interest and we have determined that we do not have significant influence over Nuro. Nuro is a privately held company, and as such, the preferred shares comprising our investment are illiquid and fair value is not readily determinable. We have elected to measure our investment in the non-marketable equity securities of Nuro at cost, less impairments, if any, plus or minus changes resulting from observable price changes in orderly transactions for the identical or similar investment of the same issuer.In November 2021, Nuro completed a Series D financing round. With respect to our Series C Preferred Stock of Nuro, we concluded that this transaction represented an observable price change in an orderly transaction for a similar investment of the same issuer. Accordingly, we recognized a gain of $5,968 relating to the increase in fair value of our investment in Nuro, within interest and other income on the consolidated statement of income for the year ended December 31, 2021. Equity Method InvestmentOn April 16, 2020, we acquired approximately 10% of the common stock of a supplier in exchange for cash consideration of $7,500. On August 6, 2020, we acquired an additional 3.2% of the common stock of the same supplier in exchange for cash consideration of $2,500. As of December 31, 2021, we own approximately 12.7% of the supplier’s common stock and have invested total cash consideration of $10,000. As we are a significant customer of the supplier and maintain board representation, we are accounting for our investment under the equity method. The investment is included within other assets on the consolidated balance sheets with a carrying value of $9,251 and $9,529 as of December 31, 2021 and 2020, respectively. There were no impairment charges in 2021 or 2020 associated with this equity method investment. Refer to Note 14. “Related Party Transactions” for related party disclosures.

Fair Value Of Financial Instruments

12 Months Ended

Dec. 31, 2021

Fair Value Of Financial Instruments [Abstract]

4. Fair Value of Financial InstrumentsAssets and Liabilities Measured at Fair Value on a Recurring Basis The carrying value of our cash and cash equivalents, restricted cash, accounts receivable and accounts payable approximate fair value because of their short-term nature.Our investments are comprised of U.S. Treasury securities, a corporate debt security, non-marketable equity securities, and an equity method investment. We also maintain a deferred compensation plan with related assets held in a rabbi trust. We designate the appropriate classification of our investments at the time of purchase based upon the intended holding period.Held-to-Maturity InvestmentsU.S. Treasury Securities As of December 31, 2021, we held $501,288 of U.S. Treasury securities with maturities of up to 24 months, of which $260,945 mature within one year. As of December 31, 2020, we held $445,944 of U.S. Treasury securities with maturities of up to 16 months, of which $343,616 matured within one year. Our investments in U.S. Treasury securities are held at amortized cost. The fair value of our held-to-maturity U.S. Treasury security investments is measured using Level 1 inputs (quoted prices for identical assets in active markets). For the years ended December 31, 2021 and 2020, the fair value of our securities were $500,172 and $445,828, respectively. We recognize a reserve for expected credit losses when lifetime credit losses are expected by management. As of December 31, 2021, management has concluded there is no risk of non-payment with respect to our U.S. Treasury security investments. Corporate Debt SecurityOn September 30, 2021, we acquired a promissory note issued by a supplier in exchange for $18,000. The promissory note has a principal balance of $18,000 and bears interest at a rate equal to the 3-month U.S. dollar London Interbank Offered Rate (“LIBOR”) plus a fixed interest spread. Accrued interest is paid quarterly in arrears and principal is payable in accordance with an amortization schedule beginning on December 31, 2022. The promissory note matures on September 30, 2028. Our investment in the corporate debt security is held at amortized cost and approximates fair value as of December 31, 2021. As of December 31, 2021, we maintained a reserve of $423 for expected credit losses associated with the investment.Rabbi TrustWe have elected to fund certain deferred compensation obligations through a rabbi trust, the assets of which are designated as trading securities, as described further in Note 9. “Employee Benefit Plans.”Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis Assets recognized or disclosed at fair value on the consolidated financial statements on a nonrecurring basis include items such as leasehold improvements, property and equipment, certain long-term investments, operating lease assets, other assets, and goodwill. These assets are measured at fair value whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. The following table summarizes our assets measured at fair value by hierarchy level on a nonrecurring basis: Carrying Value December 31, Level2021 2020Leasehold improvements, property and equipment, net3$ 1,041 $ 4,682Operating lease assets3 2,791 10,372Total $ 3,832 $ 15,054Fair value of these assets was measured using Level 3 inputs (unobservable inputs for the asset or liability). Unobservable inputs include the discount rate, projected restaurant revenues and expenses, and sublease income if we are closing the restaurant. For the years ended December 31, 2021, 2020 and 2019 we recorded asset impairments related to restaurants and offices of $4,727, $16,683 and $2,897, respectively. Carrying value after the impairment charges approximates fair value.Non-Marketable Equity SecuritiesOn March 23, 2021, we acquired 766 shares of the Series C Preferred Stock of Nuro, Inc. (“Nuro”) in exchange for cash consideration of $10,000. Our investment represents a minority interest and we have determined that we do not have significant influence over Nuro. Nuro is a privately held company, and as such, the preferred shares comprising our investment are illiquid and fair value is not readily determinable. We have elected to measure our investment in the non-marketable equity securities of Nuro at cost, less impairments, if any, plus or minus changes resulting from observable price changes in orderly transactions for the identical or similar investment of the same issuer.In November 2021, Nuro completed a Series D financing round. With respect to our Series C Preferred Stock of Nuro, we concluded that this transaction represented an observable price change in an orderly transaction for a similar investment of the same issuer. Accordingly, we recognized a gain of $5,968 relating to the increase in fair value of our investment in Nuro, within interest and other income on the consolidated statement of income for the year ended December 31, 2021. Equity Method InvestmentOn April 16, 2020, we acquired approximately 10% of the common stock of a supplier in exchange for cash consideration of $7,500. On August 6, 2020, we acquired an additional 3.2% of the common stock of the same supplier in exchange for cash consideration of $2,500. As of December 31, 2021, we own approximately 12.7% of the supplier’s common stock and have invested total cash consideration of $10,000. As we are a significant customer of the supplier and maintain board representation, we are accounting for our investment under the equity method. The investment is included within other assets on the consolidated balance sheets with a carrying value of $9,251 and $9,529 as of December 31, 2021 and 2020, respectively. There were no impairment charges in 2021 or 2020 associated with this equity method investment. Refer to Note 14. “Related Party Transactions” for related party disclosures.