Intangible Assets, Net - Additional Information (Details)	12 Months Ended
Dec. 31, 2018 CNY (¥)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 CNY (¥)	Dec. 31, 2016 CNY (¥)
Finite Lived Intangible Assets [Line Items]
Amortization of intangible assets	¥ 346,672,000	$ 50,421,000	¥ 112,860,000	¥ 102,242,000
Intangible Assets Excluding Licensed Copyrights
Finite Lived Intangible Assets [Line Items]
Amortization of intangible assets	346,672,000	50,421,000	112,860,000	102,242,000
Impairment charges on intangible assets	¥ 0	$ 0	¥ 0	¥ 0

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274

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