Goodwill and Intangible Assets - Additional Information (Detail) ¥ in Millions, $ in Millions	12 Months Ended
Dec. 31, 2019 CNY (¥) Unit	Dec. 31, 2019 USD ($) Unit	Dec. 31, 2018 CNY (¥) Unit	Dec. 31, 2017 CNY (¥)
Amortization Of Intangible Assets Disclosure [Abstract]
Number of reporting units the company	2	2	2
Impairment loss on intangible assets excluding licensed copyrights	¥ 406	$ 58	¥ 5	¥ 139
Amortization expense of intangible assets and licensed copyrights	¥ 13,500	$ 1,900	¥ 12,500	¥ 7,900

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production, including long-term licensed copyright) and short-term licensed copyrights 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.

No definition available.

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