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Income Taxes - Additional Information (Details) ¥ / shares in Units, $ / shares in Units, $ in Thousands | 12 Months Ended
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Dec. 31, 2022 CNY (¥) ¥ / shares | Dec. 31, 2022 USD ($) $ / shares | Dec. 31, 2021 CNY (¥) ¥ / shares | Dec. 31, 2020 CNY (¥) ¥ / shares
Income Taxes [Line Items] |  |  |  |
Statutory income tax rate | 25.00% | 25.00% | 25.00% | 25.00%
Income tax expenses | ¥ 11,992,000 | $ 1,739 | ¥ (19,618,000) | ¥ (236,000)
Income tax benefit/expenses if the tax holidays granted to Wuhan Shangde were not available | ¥ 24,338 |  | ¥ (11,560) |
Basic | (per share) | ¥ 94.14 | $ 13.65 | ¥ 32.56 | ¥ (63.74)
Diluted | (per share) | ¥ 94.14 | $ 13.65 | ¥ 32.56 | ¥ (63.74)
Uncertain tax positions | ¥ 0 |  | ¥ 0 | ¥ 0
Income tax rate outside the PRC | 25.00% | 25.00% |  |
PRC available for distribution earnings | ¥ 167,946,000 |  |  |
Wuhan Shangde Online Education Technology Co., Ltd. ("Wuhan Shangde") |  |  |  |
Income Taxes [Line Items] |  |  |  |
Basic | ¥ / shares |  |  | ¥ 31.36 |
Diluted | ¥ / shares | ¥ 92.34 |  |  |
Maximum |  |  |  |
Income Taxes [Line Items] |  |  |  |
Payment of dividends withholding tax, percentage | 10.00% | 10.00% |  |
Minimum |  |  |  |
Income Taxes [Line Items] |  |  |  |
Payment of dividends withholding tax, percentage | 5.00% | 5.00% |  |
Hong Kong |  |  |  |
Income Taxes [Line Items] |  |  |  |
Income tax expenses | ¥ 0 |  | ¥ 0 | ¥ 0
Hong Kong | For the First 2 Million Profits |  |  |  |
Income Taxes [Line Items] |  |  |  |
Statutory income tax rate | 8.25% | 8.25% |  |
Hong Kong | For the Remaining Profits |  |  |  |
Income Taxes [Line Items] |  |  |  |
Statutory income tax rate | 16.50% | 16.50% |  |
China |  |  |  |
Income Taxes [Line Items] |  |  |  |
Statutory income tax rate | 25.00% | 25.00% |  |
China | subsidiaries and the Variable Interest Entities |  |  |  |
Income Taxes [Line Items] |  |  |  |
Statutory income tax rate | 25.00% | 25.00% |  |
Operating loss carryforwards | ¥ 2,544,003 |  |  |
Expiration start date | Dec. 31, 2023 | Dec. 31, 2023 |  |
Expiration end date | Dec. 31, 2029 | Dec. 31, 2029 |  |
China | 2016 | Beijing Shangde Online Education Technology Company Limited |  |  |  |
Income Taxes [Line Items] |  |  |  |
Statutory income tax rate | 25.00% | 25.00% |  |
Preferential tax rate description | Beijing Sunlands was qualified as “high and new technology enterprise strongly supported by the State” (“HNTE”) and was accordingly entitled to a preferential tax rate of 15% from calendar years 2016 through 2020. For 2021 and 2022, Beijing Sunlands was subject to an EIT rate of 25%. | Beijing Sunlands was qualified as “high and new technology enterprise strongly supported by the State” (“HNTE”) and was accordingly entitled to a preferential tax rate of 15% from calendar years 2016 through 2020. For 2021 and 2022, Beijing Sunlands was subject to an EIT rate of 25%. |  |
Preferential tax rate | 15.00% | 15.00% |  |
Preferential tax exemption approved start year | 2016 | 2016 |  |
Preferential tax exemption approved end year | 2020 | 2020 |  |
China | 2021 | Wuhan Shangde Online Education Technology Co., Ltd. ("Wuhan Shangde") |  |  |  |
Income Taxes [Line Items] |  |  |  |
Statutory income tax rate | 15.00% | 15.00% |  |
Preferential tax rate description | Wuhan Shangde was qualified as HNTE and is accordingly entitled to a preferential tax rate of 15% from calendar years 2021 through 2023 and expected to be subject to an EIT rate of 15% as long as it maintains its status as a HNTE. | Wuhan Shangde was qualified as HNTE and is accordingly entitled to a preferential tax rate of 15% from calendar years 2021 through 2023 and expected to be subject to an EIT rate of 15% as long as it maintains its status as a HNTE. |  |
Preferential tax rate | 15.00% | 15.00% |  |
Preferential tax exemption approved start year | 2021 | 2021 |  |
Preferential tax exemption approved end year | 2023 | 2023 |  |

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