SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Summary of movement of allowance for uncollectible receivables (Detail) - CNY (¥) ¥ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Opening balance	¥ (28,014)
Current year net provision	(144,636)	¥ (51,430)
Current year write-off	111,971	23,416
Ending balance	(60,679)	(28,014)
Current loan products
Accounts, Notes, Loans and Financing Receivable [Line Items]
Opening balance	(28,014)
Current year net provision	(144,399)	(51,430)
Current year write-off	111,969	23,416
Ending balance	(60,444)	¥ (28,014)
Other online standard loan products
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current year net provision	(237)
Current year write-off	2
Ending balance	¥ (235)

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.

No definition available.

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- Definition

Amount of allowance for credit loss on accounts receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5074-111524

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118955202&loc=SL82895884-210446

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- Definition

Amount of direct write-downs of accounts receivable charged against the allowance.

+ References

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- Definition

Amount of expense (reversal of expense) for expected credit loss on accounts receivable.

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