Deferred revenue and customer advances (Details) ¥ in Millions, $ in Millions	Mar. 31, 2018 USD ($)	Mar. 31, 2018 CNY (¥)	Mar. 31, 2017 CNY (¥)
Deferred revenue and customer advances
Deferred revenue		¥ 13,350	¥ 9,643
Customer advances		9,940	6,050
Total		23,290	15,693
Less: current portion	$ (3,555)	(22,297)	(15,052)
Non-current portion	$ 158	¥ 993	¥ 641

Total carrying amount of deferred revenue and refundable consideration received as of the balance sheet date.

No definition available.

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- Definition

The carrying amount of consideration received or receivable as of the balance sheet date on potential earnings that were not recognized as revenue in conformity with GAAP, and which are expected to be recognized as such within one year or the normal operating cycle, if longer. And the current portion of prepayments received from customers for goods or services to be provided in the future.

+ References

No definition available.

+ Details

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- Definition

Refundable consideration, usually cash, held by the entity pending satisfactory completion of the entity's obligations or pending the closing of a contract.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.15a)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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- Definition

Amount of deferred revenue as of balance sheet date. Deferred revenue represents collections of cash or other assets related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 13.A.3)
-URI http://asc.fasb.org/extlink&oid=65893310&loc=d3e214044-122780

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 13.A.4(a).Q1)
-URI http://asc.fasb.org/extlink&oid=65893310&loc=d3e214044-122780

+ Details

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- References

No definition available.

+ Details

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- Definition

The noncurrent portion of deferred revenue amount as of balance sheet date. Deferred revenue is a liability related to a revenue producing activity for which revenue has not yet been recognized, and is not expected to be recognized in the next twelve months. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 8
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82887183&loc=d3e6935-107765

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 13.A.3(c).Q3)
-URI http://asc.fasb.org/extlink&oid=65893310&loc=d3e214044-122780

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 13.A.4(a).Q1)
-URI http://asc.fasb.org/extlink&oid=65893310&loc=d3e214044-122780

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-URI http://asc.fasb.org/extlink&oid=65893310&loc=d3e214044-122780

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
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-Section S99
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-Subparagraph (SAB Topic 13.A.3(b).Q1(c))
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-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=65893310&loc=d3e214044-122780

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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=65893310&loc=d3e214044-122780

+ Details

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