The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

No definition available.

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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

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- Definition

The carrying amount, as of the date of the latest financial statement presented, of all assets that are pledged as collateral for the payment of the related debt obligation primarily arising from secured borrowings, repurchase agreements or other current or potential obligations, where the secured party does not have the right by contract or custom to sell or re-pledge the collateral and therefore are not reclassified and separately reported in the statement of financial position.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (b)(1)(i)
-URI http://asc.fasb.org/extlink&oid=64858031&loc=SL6224234-111729

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- Definition

Amount of transactions with related party during the financial reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39603-107864

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
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-Publisher FASB
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-Topic 850
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-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39622-107864

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- Definition

The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph b
-URI http://asc.fasb.org/extlink&oid=77990344&loc=d3e5728-111685

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 6
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=77990344&loc=d3e5747-111685

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- Definition

Carrying amount of the assets in the reporting entity's statement of financial position that relate to the reporting entity's variable interest in the Variable Interest Entity (VIE), where the reporting entity is not the VIE's primary beneficiary.

+ References

+ Details

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- Definition

Carrying amount of the liabilities in the reporting entity's statement of financial position that relate to the reporting entity's variable interest in the Variable Interest Entity (VIE), where the reporting entity is not the VIE's primary beneficiary.

+ References

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Agreement expiration date.

+ References

No definition available.

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Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Agreement term.

+ References

No definition available.

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Number Of Variable Interest Entities

+ References

No definition available.

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- Definition

Exercise price of option.

+ References

No definition available.

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Balance Type:	debit
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- Definition

Organization [Line Items]

+ References

No definition available.

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- Definition

Hourly rate of service fee earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

+ References

No definition available.

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Balance Type:	credit
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- Details

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- Details

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Organization - Additional Information (Detail)		1 Months Ended	12 Months Ended
Organization - Additional Information (Detail)	Dec. 19, 2016	Jan. 31, 2011 CNY (¥)	Dec. 31, 2017 CNY (¥)	Dec. 31, 2017 USD ($) Entity	Dec. 31, 2017 CNY (¥) Entity	Mar. 31, 2017
Organization [Line Items]
Number of additional VIEs controlled through Primary Beneficiaries \| Entity				2	2
Assets pledged as collateral				$ 48,321,000	¥ 335,491,000
Unconsolidated VIE's carrying amount of assets				0	0
Unconsolidated VIE's carrying amount of liabilities				0	0
Maximum exposure to loss related to arrangements with variable interest entity				$ 9,198,000	¥ 59,846,000
Internet Data Center Services
Organization [Line Items]
Equity interest percentage by parent						51.00%
Warburg Pincus
Organization [Line Items]
Equity interest percentage						49.00%
Option Agreement
Organization [Line Items]
Exclusive option price			¥ 1,000
Agreement agreement between 21Vianet China and the 21Vianet Technology, term	10 years		10 years
Agreement agreement between 21Vianet China and the 21Vianet Technology, expiration date	Dec. 18, 2026		Dec. 18, 2016
Technical Consulting and Service Agreement
Organization [Line Items]
Agreement agreement between 21Vianet China and the 21Vianet Technology, term	10 years		10 years
Agreement agreement between 21Vianet China and the 21Vianet Technology, expiration date	Dec. 18, 2026		Dec. 18, 2016
Service fee per hour			¥ 1,000
Loan Agreement \| Shareholders \| Loan one
Organization [Line Items]
Loan facility provided to related parties		¥ 7,000,000
Loan Agreement \| Shareholders \| Loan Two
Organization [Line Items]
Loan facility provided to related parties		¥ 3,000,000