Prepayments and other current assets (Details) ¥ in Thousands, $ in Thousands	Dec. 31, 2017 CNY (¥)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 CNY (¥)
Prepayments and other current assets [Line Items]
Prepayments and deposits to vendors and content providers	¥ 81,319		¥ 70,347
Interests receivable	78,274		17,050
Employee advances	16,697		12,245
Rental and other deposits	14,214		13,015
Receivables from disposal of subsidiaries and investments	7,986		95,166
Others	23,449		16,909
Total	¥ 221,939	$ 34,111	¥ 224,732

Carrying amount as of the balance sheet date of current interest earned but not received. Also called accrued interest or accrued interest receivable. For classified balance sheets, represents the current amount receivable, that is amounts expected to be collected within one year or the normal operating cycle, if longer.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of other miscellaneous assets expected to be realized or consumed within one year or operating cycle, if longer.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(8))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(7))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82887183&loc=d3e6676-107765

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Represents the amount of asset related to consideration paid in advance to employee.

+ References

No definition available.

+ Details

Name:	yy_EmployeeAdvancesCurrent
Namespace Prefix:	yy_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- References

No definition available.

+ Details

Name:	yy_PrepaidExpenseAndOtherAssetsCurrentLineItems
Namespace Prefix:	yy_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of asset related to prepayments and deposits to suppliers and providers.

+ References

No definition available.

+ Details

Name:	yy_PrepaymentsAndDepositsToSuppliersAndProviders
Namespace Prefix:	yy_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Carrying amount as of the balance sheet date of amount receivables from disposal of subsidiaries and investments.

+ References

No definition available.

+ Details

Name:	yy_ReceivablesFromDisposalOfSubsidiary
Namespace Prefix:	yy_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of cash paid for rent and other deposits.

+ References

No definition available.

+ Details

Name:	yy_RentAndOtherDepositsCurrent
Namespace Prefix:	yy_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant