INCOME TAX EXPENSE - Deferred tax assets and deferred tax liabilities (Details) - CNY (¥) ¥ in Thousands	Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Deferred tax assets
Net accumulated losses - carry forward	¥ 1,449,953	¥ 904,496
Deductible advertising expense	551,431	543,743
Provision for credit losses	94,706	511,528
Accruals		46,097
Less: valuation allowance	¥ (2,096,090)	¥ (2,005,864)	¥ (1,974,108)	¥ (1,534,011)	¥ (1,252,253)

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Publisher FASB
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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from accrued liabilities.

+ References

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- Definition

Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary difference from allowance for credit loss on financing receivable.

+ References

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- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
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-Paragraph 2
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- Definition

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from deductible advertising expense.

+ References

No definition available.

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