Share-based awards- Expense by function (Details) - CNY (¥) ¥ in Millions	12 Months Ended
Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Share-based awards
Share-based compensation expense	¥ 15,995	¥ 16,082	¥ 13,028
Cost of revenue
Share-based awards
Share-based compensation expense	3,893	4,003	4,176
Product development expenses
Share-based awards
Share-based compensation expense	5,712	5,703	3,876
Sales and marketing expenses
Share-based awards
Share-based compensation expense	1,772	1,963	1,235
General and administrative expenses
Share-based awards
Share-based compensation expense	4,618	4,413	3,741
Share based awards relating to Ant Financial Services
Share-based awards
Unamortized compensation costs	¥ 1,039
Weighted average period over which unamortized compensation costs expected be recognized	1 year 7 months 6 days
Share-based compensation expense	¥ 2,188	¥ 5,506	¥ 3,788

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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=27013229&loc=d3e301413-122809

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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.

+ References

No definition available.

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