Fair value measurement - Fair value hierarchy (Details) - Recurring basis - CNY (¥) ¥ in Millions	Sep. 30, 2020	Mar. 31, 2020
Assets
Short-term investments	¥ 104,403	¥ 28,478
Restricted cash and escrow receivables	13,380	15,479
Listed equity securities	95,575	66,303
Convertible and exchangeable bonds	5,936	4,704
Option agreements	2,215	1,666
Others	7,059	8,110
Assets	228,568	124,740
Liabilities
Contingent consideration in relation to investments and acquisitions	2,482	4,400
Interest rate swap contracts and others	427	494
Liabilities	2,909	4,894
Level 1
Assets
Short-term investments	4	64
Restricted cash and escrow receivables	13,380	15,479
Listed equity securities	95,575	66,303
Others	492	144
Assets	109,451	81,990
Level 2
Assets
Short-term investments	104,399	28,414
Convertible and exchangeable bonds	487	709
Option agreements	2,100	1,521
Others	3,752	5,114
Assets	110,738	35,758
Liabilities
Interest rate swap contracts and others	207	156
Liabilities	207	156
Level 3
Assets
Convertible and exchangeable bonds	5,449	3,995
Option agreements	115	145
Others	2,815	2,852
Assets	8,379	6,992
Liabilities
Contingent consideration in relation to investments and acquisitions	2,482	4,400
Interest rate swap contracts and others	220	338
Liabilities	¥ 2,702	¥ 4,738

Fair value as of the balance sheet date of call option agreements.

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- Definition

Fair value portion of convertible and exchangeable bonds.

+ References

No definition available.

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Fair value as of the balance sheet date of interest rate derivative liabilities, which includes all such derivative instruments in hedging and non hedging relationships that are recognized as liabilities, and liabilities classified as others.

+ References

No definition available.

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- Definition

Amount of current and noncurrent liability recognized arising from contingent consideration attributable to an investment by the entity or a business combination.

+ References

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Fair value portion of cash and cash equivalent items which are restricted as to withdrawal or usage, and escrow receivables which are classified as current.

+ References

No definition available.

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Fair value portion of certificate of deposit or savings account held with a bank or other financial institution with a maturity between three months and one year.

+ References

No definition available.

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
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- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=99377092&loc=SL75136599-209740

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Fair value of financial and nonfinancial obligations.

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Fair value portion of other assets.

+ References

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