Share-based awards - Share-based awards relating to Ant Financial (Details) - CNY (¥) ¥ in Millions	12 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Share-based awards
Share-based compensation expense	¥ 31,742	¥ 37,491	¥ 20,075
Share-based awards relating to Ant Group
Share-based awards
Share-based compensation expense	¥ 1,261	¥ 12,855	¥ 2,278
Share-based awards relating to Ant Group \| Share-based awards with four-year vesting schedule
Share-based awards
Vesting period	4 years	4 years	4 years
Vesting percentage	25.00%	25.00%	25.00%
Share-based awards relating to Ant Group \| Share-based awards with four-year vesting schedule and initial vesting at first anniversary
Share-based awards
Vesting percentage	25.00%	25.00%	25.00%
Share-based awards relating to Ant Group \| Share-based awards with four-year vesting schedule and initial vesting at second anniversary
Share-based awards
Vesting percentage	50.00%	50.00%	50.00%
Share-based awards relating to Ant Group \| Share-based awards with six-year vesting schedule
Share-based awards
Vesting period	6 years	6 years	6 years

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5047-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

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.

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Percentage of vesting of award under share-based payment arrangement.

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