Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ 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(13))
-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(14))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Section S99
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-Subparagraph (SX 210.7-03(a)(8))
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Property and equipment, net (Schedule of Property and Equipment) (Details) ¥ in Thousands, $ in Thousands	Dec. 31, 2017 CNY (¥)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 CNY (¥)
Property and equipment, net [Line Items]
Gross carrying amount	¥ 1,535,126		¥ 1,250,773
Less: accumulated depreciation	(518,128)		(412,023)
Property and equipment, net	1,016,998	$ 156,310	838,750
Buildings [Member]
Property and equipment, net [Line Items]
Gross carrying amount	731,640		482,333
Servers, computers and equipment [Member]
Property and equipment, net [Line Items]
Gross carrying amount	588,589		565,786
Leasehold improvements [Member]
Property and equipment, net [Line Items]
Gross carrying amount	18,651		80,812
Decoration of buildings [Member]
Property and equipment, net [Line Items]
Gross carrying amount	100,711		68,981
Furniture, fixture and office equipment [Member]
Property and equipment, net [Line Items]
Gross carrying amount	24,102		23,259
Motor vehicles [Member]
Property and equipment, net [Line Items]
Gross carrying amount	27,330		24,016
Construction in progress [Member]
Property and equipment, net [Line Items]
Gross carrying amount	¥ 44,103		¥ 5,586