Decrease in noncontrolling interest (for example, but not limited to, redeeming or purchasing the interests of noncontrolling shareholders, issuance of shares (interests) by the non-wholly owned subsidiary to the parent entity for other than cash, and a buyback of shares (interest) by the non-wholly owned subsidiary from the noncontrolling interests).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=108774443&loc=SL4569655-111683

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
-Paragraph 24
-URI http://asc.fasb.org/extlink&oid=108774443&loc=SL4616395-111683

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Significant equity transactions, mergers and acquisitions and investments - Lazada (Details) - Lazada ¥ in Millions, $ in Millions	1 Months Ended	12 Months Ended
	Jun. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Mar. 31, 2020 CNY (¥)	Mar. 31, 2019 USD ($)	Mar. 31, 2019 CNY (¥)	Mar. 31, 2018 USD ($)	Mar. 31, 2018 CNY (¥)
Business Acquisition [Line Items]
Capital injections made and additional equity acquired		$ 2,056	¥ 14,368	$ 790	¥ 5,355	$ 1,586	¥ 10,579
Reduction of noncontrolling interest			¥ 466				¥ 1,681
Addition of noncontrolling interest					¥ 400
Subsequent event
Business Acquisition [Line Items]
Capital injections made and additional equity acquired \| $	$ 250