Income tax expenses if the tax holidays granted were not available.

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Represents the preferential tax rate applicable to the entity under the preferential tax treatment.

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Income taxes.

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Operating loss carryforwards expiration end date.

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Operating loss carryforwards expiration start date.

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Preferential tax exemption approved end period.

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Preferential tax exemption approved start period.

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Preferential tax rate.

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Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to statutory income tax expense (benefit) outside of the country of domicile.

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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The amount of the unrecognized tax benefit of a position taken for which it is reasonably possible that the total amount thereof will significantly increase or decrease within twelve months of the balance sheet date.

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Income Taxes - Additional Information (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019 CNY (¥)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 CNY (¥)	Dec. 31, 2017 CNY (¥)
Income Taxes [Line Items]
Statutory income tax rate	25.00%	25.00%	25.00%	25.00%
Income tax expenses	¥ 2,440,000	$ 350	¥ 0	¥ 0
Income tax expenses if the tax holidays granted to Beijing Sunlands were not available	0
Uncertain tax positions	¥ 0		0	0
Income tax rate outside the PRC	25.00%	25.00%
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%
Deferred income tax expense	¥ 2,440,000		¥ 0	¥ 0
China \| subsidiaries and the Variable Interest Entities
Income Taxes [Line Items]
Statutory income tax rate	25.00%	25.00%
Operating loss carryforwards	¥ 2,923,067
Expiration start date	Dec. 31, 2020	Dec. 31, 2020
Expiration end date	Dec. 31, 2029	Dec. 31, 2029
China \| 2016 \| Beijing Sunlands
Income Taxes [Line Items]
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 2021 and is expected to be subject to an EIT rate of 15% as long as it maintains its status as a HNTE.	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 2021 and is 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	2016	2016
Preferential tax exemption approved end year	2021	2021