Investment securities and fair value disclosure- Fair value hierarchy (Details) - CNY (¥) ¥ in Millions	Mar. 31, 2018	Mar. 31, 2017
Assets
Investment securities accounted for under the fair value option	¥ 1,821	¥ 183
Recurring basis
Assets
Short-term investments	6,086	3,011
Restricted cash and escrow receivables	3,417	2,655
Investment securities accounted for under the fair value option	1,821	183
Interest rate swaps	542	436
Assets	40,589	29,547
Liabilities
Forward exchange contracts		78
Contingent consideration in relation to investments and acquisitions	120	921
Liabilities	120	999
Recurring basis \| Level 1
Assets
Short-term investments	6,086	3,011
Restricted cash and escrow receivables	3,417	2,655
Assets	38,226	28,928
Recurring basis \| Level 2
Assets
Interest rate swaps	542	436
Assets	542	436
Liabilities
Forward exchange contracts		78
Liabilities		78
Recurring basis \| Level 3
Assets
Investment securities accounted for under the fair value option	1,821	183
Assets	1,821	183
Liabilities
Contingent consideration in relation to investments and acquisitions	120	921
Liabilities	120	921
Listed equity securities
Assets
Available-for-sale securities	28,723	23,262
Listed equity securities \| Recurring basis
Assets
Available-for-sale securities	28,723	23,262
Listed equity securities \| Recurring basis \| Level 1
Assets
Available-for-sale securities	¥ 28,723	¥ 23,262

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.

+ References

No definition available.

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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

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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

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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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=75030427&loc=d3e22054-111558

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-Topic 320
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-Topic 320
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- Definition

Fair value portion of liability contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward (delivery or nondelivery) contracts, and swaps entered into.

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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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13433-108611

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Fair value of financial and nonfinancial obligations.

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