Long-Term Investments - Summary of Available-For-Sale Debt Investments (Detail) - CNY (¥) ¥ in Thousands	12 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Debt Securities, Available-for-sale [Abstract]
Cost	¥ 60,000	¥ 60,000
Gross unrealized gains	11,357	10,328
Gross unrealized losses	0	0
Fair value	¥ 71,357	¥ 70,328

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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

Amount of unrealized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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