Represents the amount of assessable profits considered for taxation purposes.

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Effective income tax rate reconciliation at federal preferential income tax rate from 2018 to 2022.

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Effective income tax rate reconciliation at federal preferential income tax rate from 2023 to 2030

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No definition available.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Represents the reduced withholding income tax rate for dividend paid to beneficial owner.

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No definition available.

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Value added tax rate.

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Represents the withholding income tax rate for dividend paid to foreign tax resident investors.

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No definition available.

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- Definition

Amount of deferred tax liability not recognized because of the exceptions to comprehensive recognition of deferred taxes related to undistributed earnings of foreign subsidiaries.

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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 attributable to changes in the income tax rates.

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Taxation - Tax rates (Details) ¥ in Millions, $ in Millions		3 Months Ended	12 Months Ended
Taxation - Tax rates (Details) ¥ in Millions, $ in Millions	Jan. 01, 2008	Sep. 30, 2020	Dec. 31, 2021 USD ($)	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2021 CNY (¥)
Income Taxes [Line Items]
Statutory tax rate (as a percentage)			25.00%	25.00%	25.00%
Preferential tax rate				2.40%
PRC
Income Taxes [Line Items]
Statutory tax rate (as a percentage)			25.00%	25.00%
Preferential tax rate		10.00%
Withholding income tax rate for dividend paid to foreign tax resident investors (as a percentage)	10.00%
Reduced withholding tax rate for beneficial owner (as a percentage)	5.00%
Unrecognized tax liabilities related to undistributed profits \| ¥								¥ 694
PRC \| Beizhipiji
Income Taxes [Line Items]
Statutory tax rate (as a percentage)			25.00%	25.00%	15.00%	15.00%	15.00%
PRC \| Shenzhen Lexin Software
Income Taxes [Line Items]
Statutory tax rate (as a percentage)			12.50%	12.50%	10.00%
PRC \| Shenzhen Dinsheng Computer Technology
Income Taxes [Line Items]
Statutory tax rate (as a percentage)			12.50%	12.50%	12.50%
PRC \| Beihai Aurora and Beihai Turing
Income Taxes [Line Items]
Preferential tax rate			15.00%
Tax exempt income rate (as a percent)			40.00%
Preferential income tax rate (as a percentage) from 2018 to 2022			9.00%	9.00%	9.00%	9.00%
Preferential income tax rate (as a percentage) from 2023 to 2030			15.00%
Hong Kong
Income Taxes [Line Items]
Statutory tax rate (as a percentage)			16.50%
Assessable profits \| $			$ 2
Withholding income tax rate for dividend paid to foreign tax resident investors (as a percentage)			8.25%
Online direct sales and services income \| PRC \| Maximum
Income Taxes [Line Items]
Value added tax rate (as a percent)			16.00%
Online direct sales and services income \| PRC \| Minimum
Income Taxes [Line Items]
Value added tax rate (as a percent)			13.00%
Premium membership fees, third-party sellers' commission fees, and financial services income \| PRC
Income Taxes [Line Items]
Value added tax rate (as a percent)			6.00%