Fixed Assets, Net - Components of Fixed Assets (Details) ¥ in Thousands, $ in Thousands	Dec. 31, 2019 CNY (¥)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 CNY (¥)
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	¥ 3,306,205	$ 474,907	¥ 2,814,797
Less: Accumulated depreciation	(1,632,225)	(234,454)	(1,263,673)
Construction in progress	80,387	11,546	67,023
Property, plant and equipment, net	1,754,367	251,999	1,618,147
Computer Equipment
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	2,436,926	350,043	2,057,218
Office Building
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	588,685	84,559	588,685
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	129,010	18,531	97,938
Office Furniture and Equipment
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	132,693	19,060	57,999
Others
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	¥ 18,891	$ 2,714	¥ 12,957

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

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Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

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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.

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