Fair Value Measurement - Schedule of Fair Value of Hierarchy For Assets and Liabilities Measured on Recurring Basis (Details) ¥ in Thousands, $ in Thousands	Dec. 31, 2021 CNY (¥)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 CNY (¥)
Assets
Restricted time deposits	¥ 1,745,898	$ 273,969	¥ 1,779,458
Recurring Basis \| Fair Value
Assets
Restricted time deposits	1,745,898		1,779,458
Loans at fair value	252,970		381,393
Total assets	1,998,868		2,160,851
Liabilities
Guarantee derivative liabilities	1,473,853		252,613
Total liabilities	1,473,853		252,613
Recurring Basis \| Fair Value \| Level 2 Inputs
Assets
Restricted time deposits	1,745,898		1,779,458
Total assets	1,745,898		1,779,458
Recurring Basis \| Fair Value \| Level 3 Inputs
Assets
Loans at fair value	252,970		381,393
Total assets	252,970		381,393
Liabilities
Guarantee derivative liabilities	1,473,853		252,613
Total liabilities	¥ 1,473,853		¥ 252,613

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities.

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Fair value portion of guarantee, including, but not limited to, financial standby letter of credit, fair value guarantee, guarantee of collection of scheduled contractual cash flows from financial assets, and contracts that contingently require the guarantor to make payments or perform services.

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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Amount of cash equivalents restricted as to withdrawal or usage, classified as current. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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