| Pay vs Performance Disclosure - USD ($) | 12 Months Ended |
| Dec. 25, 2022 | Dec. 26, 2021 | Dec. 27, 2020 |
| Pay vs Performance Disclosure [Table] | | | |
| Pay vs Performance [Table Text Block] | Value of Initial Fixed $100 Investment Based On: Year (1) Summary Compensation Table Total for PEO Compensation Actually Paid to PEO (2) (3) Average Summary Compensation Table Total for non-PEO NEOs Average Compensation Actually Paid to non-PEO NEOs (2)(3) Total Shareholder Return (5) Peer Group Total Shareholder Return (5) Net Income (Loss) Adjusted EBITDA (6) ($) ($) ($) ($) ($) ($) ($) ($) 2022 350,144 (61,516,400) (4) 649,693 (5,807,584) (4) 32 76 (190,441,000) (49,934,000) 2021 38,819,816 111,239,574 (5) 38,814,481 111,234,239 (4) 112 98 (153,175,000) (63,099,000) | | |
| Named Executive Officers, Footnote [Text Block] | NEOs included in the above compensation columns reflect the following: Year PEO Non-PEOs 2022 Jon Neman Mitch Reback, Wouleta Ayele, Jim McPhail and Daniel Shlossman 2021 Jon Neman Nicolas Jammet and Nathaniel Ru | | |
| Peer Group Issuers, Footnote [Text Block] | Company and peer group TSR reflects the Company’s "2022 peer group" as reflected in our 2022 Annual Report on Form the 10-K pursuant to Item 201(e) of Regulation S-K. Each year reflects what the cumulative value of $100 would be, including reinvestment of dividends, if such amount were invested on our IPO date of November 19, 2021 through the last day of the fiscal year presented. | | |
| PEO Total Compensation Amount | $ 350,144 | $ 38,819,816 | |
| PEO Actually Paid Compensation Amount | $ (61,516,400) | 111,239,574 | |
| Adjustment To PEO Compensation, Footnote [Text Block] | "Compensation Actually Paid" to our PEO (Jonathan Neman) and the average “Compensation Actually Paid” to our non-PEO NEOs in 2022 and 2021 reflects the following adjustments from Total compensation reported in the Summary Compensation Table (in thousands): 2022 2021 PEO Average Non-PEO PEO Average Non-PEO Total Reported in Summary Compensation Table (SCT) $ 350,144 $ 649,693 $ 38,819,816 $ 38,814,481 Less, Value of Stock and Option Awards reported in SCT — (240,953) (38,142,732) (38,142,732) Plus, Year-End Fair Value of Awards Granted During Fiscal Year that are Unvested and Outstanding — 68,574 77,526,763 77,526,763 Plus, Change in Fair Value (from Prior Fiscal Year-End to Current Fiscal Year-End) of Prior Year Awards that are Outstanding and Unvested (57,677,180) (4,941,831) 7,770,827 7,770,827 Plus, Vesting Date Fair Value of Awards Granted During Fiscal Year and that Vested During Fiscal Year — 21,083 — — Plus, Change in Fair Value (from Prior Fiscal Year-End to Vesting Date) of Prior Year Awards that Vested During Fiscal Year (4,189,364) (1,364,150) 25,264,900 25,264,900 Less Prior Year Fair Value of Prior Year Awards that Failed to Vest this Year — — — — Total Adjustments (61,866,544) (6,457,277) 72,419,758 72,419,758 "Compensation Actually Paid” for Fiscal Year $ (61,516,400) $ (5,807,584) $ 111,239,574 $ 111,234,239 | | |
| Non-PEO NEO Average Total Compensation Amount | $ 649,693 | 38,814,481 | |
| Non-PEO NEO Average Compensation Actually Paid Amount | $ (5,807,584) | 111,234,239 | |
| Adjustment to Non-PEO NEO Compensation Footnote [Text Block] | "Compensation Actually Paid" to our PEO (Jonathan Neman) and the average “Compensation Actually Paid” to our non-PEO NEOs in 2022 and 2021 reflects the following adjustments from Total compensation reported in the Summary Compensation Table (in thousands): 2022 2021 PEO Average Non-PEO PEO Average Non-PEO Total Reported in Summary Compensation Table (SCT) $ 350,144 $ 649,693 $ 38,819,816 $ 38,814,481 Less, Value of Stock and Option Awards reported in SCT — (240,953) (38,142,732) (38,142,732) Plus, Year-End Fair Value of Awards Granted During Fiscal Year that are Unvested and Outstanding — 68,574 77,526,763 77,526,763 Plus, Change in Fair Value (from Prior Fiscal Year-End to Current Fiscal Year-End) of Prior Year Awards that are Outstanding and Unvested (57,677,180) (4,941,831) 7,770,827 7,770,827 Plus, Vesting Date Fair Value of Awards Granted During Fiscal Year and that Vested During Fiscal Year — 21,083 — — Plus, Change in Fair Value (from Prior Fiscal Year-End to Vesting Date) of Prior Year Awards that Vested During Fiscal Year (4,189,364) (1,364,150) 25,264,900 25,264,900 Less Prior Year Fair Value of Prior Year Awards that Failed to Vest this Year — — — — Total Adjustments (61,866,544) (6,457,277) 72,419,758 72,419,758 "Compensation Actually Paid” for Fiscal Year $ (61,516,400) $ (5,807,584) $ 111,239,574 $ 111,234,239 | | |
| Compensation Actually Paid vs. Total Shareholder Return [Text Block] | Note: sweetgreen's TSR was not available in 2020 | | |
| Compensation Actually Paid vs. Net Income [Text Block] | | | |
| Compensation Actually Paid vs. Company Selected Measure [Text Block] | | | |
| Total Shareholder Return Vs Peer Group [Text Block] | Note: sweetgreen's TSR was not available in 2020 | | |
| Total Shareholder Return Amount | $ 32 | 112 | |
| Peer Group Total Shareholder Return Amount | 76 | 98 | |
| Net Income (Loss) | $ (190,441,000) | $ (153,175,000) | |
| Company Selected Measure Amount | (49,934,000) | (63,099,000) | |
| PEO Name | Jon Neman | Jon Neman | |
| Additional 402(v) Disclosure [Text Block] | Except as described in footnote (3) below, fair value or change in fair value, as applicable, of equity awards in the "Compensation Actually Paid" columns was calculated in accordance with ASC Topic 718, and the valuation methods used to calculate the fair values did not materially differ from those disclosed at the time of grant. For the portion of "Compensation Actually Paid" that represents compensation based on year-end stock prices, the following prices were used: for 2022, $8.83 (72% reduction from prior year); for 2021, $31.36 (304% increase from IPO date); and for 2020, $7.77 (which is prior to the IPO date, and was based on the active 409A price as of that date). We believe the “Compensation Actually Paid” in each of the years reported above is reflective of the Compensation Committee’s emphasis on “pay-for-performance” as the “Compensation Actually Paid” is in line with business performance, primarily due our stock price performance and our achievement against pre-established performance goals under our Annual Bonus Plan. See “— Compensation Discussion and Analysis ” above for additional information regarding our Annual Bonus Plan and other elements of our executive compensation program. | | |
| Average Compensation, Share Price | $ 8.83 | $ 31.36 | $ 7.77 |
| Increase (Decrease) In Average Compensation, Share Price, Percent | 72% | 304% | |
| Measure [Axis]: 1 | | | |
| Pay vs Performance Disclosure [Table] | | | |
| Measure Name | Adjusted EBITDA | | |
| Non-GAAP Measure Description [Text Block] | Adjusted EBITDA, a non-GAAP measure, is defined as net loss adjusted to exclude interest income, interest expense, provision for income taxes, depreciation and amortization, stock-based compensation expense, loss on disposal of property and equipment, Spyce acquisition costs, amortization of cloud-based software implementation costs, other expense, and in certain periods, impairment and closure costs, and restructuring charges. | | |
| Measure [Axis]: 2 | | | |
| Pay vs Performance Disclosure [Table] | | | |
| Measure Name | Net Sales | | |
| Measure [Axis]: 3 | | | |
| Pay vs Performance Disclosure [Table] | | | |
| Measure Name | sweetgreen stock price performance | | |
| PEO [Member] | | | |
| Pay vs Performance Disclosure [Table] | | | |
| Adjustment to Compensation Amount | $ (61,866,544) | $ 72,419,758 | |
| PEO [Member] | Stock Awards Adjustments [Member] | | | |
| Pay vs Performance Disclosure [Table] | | | |
| Adjustment to Compensation Amount | 0 | (38,142,732) | |
| PEO [Member] | Equity Awards Granted in Current Year, Unvested [Member] | | | |
| Pay vs Performance Disclosure [Table] | | | |
| Adjustment to Compensation Amount | 0 | 77,526,763 | |
| PEO [Member] | Equity Awards Granted in Prior Years, Unvested [Member] | | | |
| Pay vs Performance Disclosure [Table] | | | |
| Adjustment to Compensation Amount | (57,677,180) | 7,770,827 | |
| PEO [Member] | Equity Awards Granted in Current Year, Vested [Member] | | | |
| Pay vs Performance Disclosure [Table] | | | |
| Adjustment to Compensation Amount | 0 | 0 | |
| PEO [Member] | Equity Awards Granted in Prior Years, Vested [Member] | | | |
| Pay vs Performance Disclosure [Table] | | | |
| Adjustment to Compensation Amount | (4,189,364) | 25,264,900 | |
| PEO [Member] | Equity Awards that Failed to Meet Vesting Conditions [Member] | | | |
| Pay vs Performance Disclosure [Table] | | | |
| Adjustment to Compensation Amount | 0 | 0 | |
| Non-PEO NEO [Member] | | | |
| Pay vs Performance Disclosure [Table] | | | |
| Adjustment to Compensation Amount | (6,457,277) | 72,419,758 | |
| Non-PEO NEO [Member] | Stock Awards Adjustments [Member] | | | |
| Pay vs Performance Disclosure [Table] | | | |
| Adjustment to Compensation Amount | (240,953) | (38,142,732) | |
| Non-PEO NEO [Member] | Equity Awards Granted in Current Year, Unvested [Member] | | | |
| Pay vs Performance Disclosure [Table] | | | |
| Adjustment to Compensation Amount | 68,574 | 77,526,763 | |
| Non-PEO NEO [Member] | Equity Awards Granted in Prior Years, Unvested [Member] | | | |
| Pay vs Performance Disclosure [Table] | | | |
| Adjustment to Compensation Amount | (4,941,831) | 7,770,827 | |
| Non-PEO NEO [Member] | Equity Awards Granted in Current Year, Vested [Member] | | | |
| Pay vs Performance Disclosure [Table] | | | |
| Adjustment to Compensation Amount | 21,083 | 0 | |
| Non-PEO NEO [Member] | Equity Awards Granted in Prior Years, Vested [Member] | | | |
| Pay vs Performance Disclosure [Table] | | | |
| Adjustment to Compensation Amount | (1,364,150) | 25,264,900 | |
| Non-PEO NEO [Member] | Equity Awards that Failed to Meet Vesting Conditions [Member] | | | |
| Pay vs Performance Disclosure [Table] | | | |
| Adjustment to Compensation Amount | $ 0 | $ 0 | |
