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Equity interests pledged percentage.

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Income From Government Grants

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Percentage of loans facilitated.

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Value added tax rate.

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Variable interest entities percentage of consolidate assets.

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Weighted average expected net accumulative loss rates.

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Weighted average investment period.

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Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes 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. Excludes cash and cash equivalents within disposal group and discontinued operation.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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Amount of deferred income and obligation to transfer product and service to customer for which consideration has been received or is receivable.

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Amount of cost for defined contribution plan.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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The amount of excise and sales taxes included in sales and revenues, which are then deducted as a cost of sales. Includes excise taxes, which are applied to specific types of transactions or items (such as gasoline or alcohol); and sales, use and value added taxes, which are applied to a broad class of revenue-producing transactions involving a wide range of goods and services.

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Foreign exchange rate used to translate amounts denominated in functional currency to reporting currency.

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The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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Amount of funds committed to investment company from investors.

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Amount after accretion (amortization) of discount (premium), and investment expense, of interest income and dividend income on nonoperating securities.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section S99
-Paragraph 2
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(31))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(30))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Additional Information (Detail) $ in Thousands	1 Months Ended	12 Months Ended
	Jul. 31, 2018 CNY (¥)	Dec. 31, 2019 CNY (¥)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 CNY (¥)	Dec. 31, 2017 CNY (¥)	Dec. 31, 2019 USD ($)	Jul. 30, 2019
Shareholders' deficit		¥ (741,854,000)		¥ (1,652,006,000)		$ (106,561)
Net income		527,747,000	$ 75,805	611,758,000	¥ 539,545,000
Net cash used in the operating activities		26,291,000	$ 3,777	(228,368,000)	104,752,000
Cash and cash equivalents		¥ 122,149,000		¥ 41,441,000	¥ 606,097,000	$ 17,546
VIEs percentage of Group's consolidated revenue		96.00%	96.00%	100.00%	100.00%
VIEs percentage of consolidated total assets		52.00%	52.00%	100.00%
VIEs percentage of consolidated total liabilities		95.00%	95.00%	100.00%
Convenience translation rate per US$1.00		6.9618				6.9618
Value added tax rate				6.00%
Value added tax amount		¥ 168,763,000		¥ 298,720,000	¥ 273,785,000
Service fees		¥ 174,191,000		¥ 242,513,000	¥ 156,563,000
Weighted average investment period		8 months 9 days	8 months 9 days	8 months	8 months 21 days
Remaining performance obligations		¥ 137,313,000		¥ 222,735,000
Remaining performance obligations, percentage that will be recognized by the Group over the following 12 months		100.00%		92.00%		100.00%
Advertising expenses		¥ 26,985,000		¥ 25,994,000	¥ 21,828,000
Government grants		18,722,000		22,465,000	12,471,000
Minimum operating lease commitements		50,682,000		50,682,000
Employee defined contribution plan expense		¥ 65,076,000		51,611,000	82,053,000
Percentage of ownership interest		20.00%				20.00%
Current portion of lease liabilities		¥ 2,735,000
Weighted average discount rate		4.75%				4.75%
Right-of-use assets		¥ 37,215,000
Lease liabilities		35,215,000
Deferred Revenue		55,689,000		¥ 41,252,000	¥ 0
Weighted average expected net accumulative loss rates				11.20%	13.40%
SG Fintech Joint Stock Company
Business acquisition, percentage of voting interests acquired							24.90%
Investment income, net		¥ 378,000
Cash and Cash Equivalents [Member] \| CHINA
Concentration risk, percentage		64.00%	64.00%
Cash and Cash Equivalents [Member] \| Overseas
Concentration risk, percentage		36.00%	36.00%
Exclusive Purchase Agreement Member [Member] \| Shanghai Kunjia Technology Co., Ltd. ("Shanghai Kunjia" or "WFOE") [Member]
Consideration of purchase		¥ 1
Effective time period of agreement		10 years	10 years
Post-origination service
Contract liability revenue recognised		¥ 4,902,000
Remaining performance obligations		¥ 182,026,000		¥ 222,735,000	¥ 171,000,000
Remaining performance obligations, percentage that will be recognized by the Group over the following 12 months		100.00%		92.00%	70.00%	100.00%
Deferred Revenue, Revenue Recognized		¥ 41,252,000
Post-origination service \| Accrued Liabilities
Contract liabilities		0
Post-origination service \| Other Current Liabilities
Contract liabilities				¥ 41,252,000
China United SME Guarantee Corporation
Unsecured loans facilitated subject to investor assurance program		¥ 2,544,000,000		¥ 1,233,000,000
Percentage of total loan volume facilitated		14.00%	14.00%	5.00%
Shenzhen Rongxinbao Non-financial Guarantee Co., Ltd.
Unsecured loans facilitated subject to investor assurance program		¥ 15,661,000,000		¥ 11,082,000,000
Percentage of total loan volume facilitated		86.00%	86.00%	47.00%
Selective unrelated third party individual investors
Investment amount	¥ 1,000,000
Unsecured loans facilitated subject to investor assurance program		¥ 2,727,000,000		¥ 2,727,000,000
Percentage of total loan volume facilitated		12.00%	12.00%	12.00%
Payment Guarantee [Member]
Guarantee obligations		¥ 487,216,000
CNY
Cash and cash equivalents				¥ 41,441,000
Variable Interest Entity, Primary Beneficiary
Unsecured loans facilitated subject to investor assurance program				¥ 8,632,000,000
Percentage of total loan volume facilitated				36.00%
Equity Pledge Agreement
Percentage of equity interest in Jiayin Finance pledged to WFOE		100.00%	100.00%