Investment securities and fair value disclosure - Fair value hierarchy (Details) - Recurring basis - CNY (¥) ¥ in Millions	Mar. 31, 2019	Mar. 31, 2018
Assets
Short-term investments	¥ 3,262	¥ 6,086
Restricted cash and escrow receivables	8,518	3,417
Listed equity securities	61,202	28,723
Equity securities accounted for under the fair value option		565
Convertible bond accounted for under the fair value option	2,742	1,256
Interest rate swaps	331	542
Others	3,207
Assets	79,262	40,589
Liabilities
Contingent consideration in relation to investments and acquisitions	5,122	120
Liabilities	5,122	120
Level 1
Assets
Short-term investments	3,262	6,086
Restricted cash and escrow receivables	8,518	3,417
Listed equity securities	61,202	28,723
Convertible bond accounted for under the fair value option	244
Others	604
Assets	73,830	38,226
Level 2
Assets
Interest rate swaps	331	542
Others	1,444
Assets	1,775	542
Level 3
Assets
Equity securities accounted for under the fair value option		565
Convertible bond accounted for under the fair value option	2,498	1,256
Others	1,159
Assets	3,657	1,821
Liabilities
Contingent consideration in relation to investments and acquisitions	5,122	120
Liabilities	¥ 5,122	¥ 120

The fair value of convertible bond accounted for under the fair value option.

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Fair value of investment securities accounted for under the fair value option.

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

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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.

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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.

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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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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 as of the balance sheet date of interest rate derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets.

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Fair value of financial and nonfinancial obligations.

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Fair value portion of other assets.

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