Goodwill - Schedule of Changes in the Carrying Amount of Goodwill (Detail) ¥ in Thousands, $ in Thousands	Mar. 31, 2021 USD ($)	Mar. 31, 2021 CNY (¥)	Mar. 31, 2020 CNY (¥)	Mar. 31, 2019 CNY (¥)
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill		¥ 40,184	¥ 40,184	¥ 494
Accumulated impairment loss		0	0	0
Total	$ 6,133	40,184	40,184	¥ 494
Additions		¥ 0	¥ 39,690

Goodwill additions transaction.

No definition available.

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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-Subparagraph (SX 210.9-03(10)(1))
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-Name Accounting Standards Codification
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-Section 45
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- References

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- Definition

Amount before accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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-Section 50
-Paragraph 1
-Subparagraph (a)
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- Definition

Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (h)
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