Financial Risk Management Objectives and Policies - Exposures to Foreign Currency (Detail) ¥ in Thousands, $ in Thousands	Dec. 31, 2020 CNY (¥)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 CNY (¥)
Disclosure of nature and extent of risks arising from financial instruments [line items]
Cash and bank balances	¥ 6,447,538	$ 996,328	¥ 6,390,918
Financial liabilities	(12,486,410)	(1,929,505)	(10,699,413)
Trade and other payables	(10,302,531)	(1,592,034)	(8,644,393)
Foreign currency risk [Member] \| Singapore dollar [Member]
Disclosure of nature and extent of risks arising from financial instruments [line items]
Quoted equity securities	6,258		9,235
Trade and other receivables	620		607
Cash and bank balances	181,575		228,589
Financial liabilities	(1,462)		(15,710)
Trade and other payables	(6,184)		(7,086)
Net assets/(liabilities)	180,807	27,940	215,635
Foreign currency risk [Member] \| Euro [Member]
Disclosure of nature and extent of risks arising from financial instruments [line items]
Trade and other receivables	8,624		414
Cash and bank balances	3,829		52
Trade and other payables	(9,356)		(27,922)
Net assets/(liabilities)	3,097	479	(27,456)
Foreign currency risk [Member] \| USD [Member]
Disclosure of nature and extent of risks arising from financial instruments [line items]
Trade and other receivables	913		7,624
Cash and bank balances	45,203		11,233
Financial liabilities			(139,524)
Trade and other payables	(10,858)		(10,596)
Net assets/(liabilities)	35,258	5,448	(131,263)
Foreign currency risk [Member] \| Renminbi [Member]
Disclosure of nature and extent of risks arising from financial instruments [line items]
Trade and other receivables	305		658
Cash and bank balances	0		2,595
Trade and other payables	(2,464)		(2,605)
Net assets/(liabilities)	(2,159)	(334)	648
Foreign currency risk [Member] \| Others [Member]
Disclosure of nature and extent of risks arising from financial instruments [line items]
Trade and other receivables	372
Cash and bank balances	15,086		7,364
Trade and other payables			(83)
Net assets/(liabilities)	¥ 15,458	$ 2,389	¥ 7,281

Cash and bank balances.

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Current financial assets at fair value through profit or loss, classified as quoted equity securities.

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No definition available.

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Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

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No definition available.

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The amount of liabilities that are: (a) a contractual obligation: (i) to deliver cash or another financial asset to another entity; or (ii) to exchange financial assets or financial liabilities with another entity under conditions that are potentially unfavourable to the entity; or (b) a contract that will, or may be, settled in the entity’s own equity instruments and is: (i) a non-derivative for which the entity is, or may be, obliged to deliver a variable number of the entity’s own equity instruments; or (ii) a derivative that will, or may be, settled other than by the exchange of a fixed amount of cash or another financial asset for a fixed number of the entity’s own equity instruments. For this purpose, rights, options or warrants to acquire a fixed number of the entity’s own equity instruments for a fixed amount of any currency are equity instruments if the entity offers the rights, options or warrants pro rata to all of its existing owners of the same class of its own non-derivative equity instruments. Also, for those purposes the entity’s own equity instruments do not include puttable financial instruments that are classified as equity instruments in accordance with paragraphs 16A-16B of IAS 32, instruments that impose on the entity an obligation to deliver to another party a pro rata share of the net assets of the entity only on liquidation and are classified as equity instruments in accordance with paragraphs 16C-16D of IAS 32, or instruments that are contracts for the future receipt or delivery of the entity’s own equity instruments. As an exception, an instrument that meets the definition of a financial liability is classified as an equity instrument if it has all the features and meets the conditions in paragraphs 16A-16B or paragraphs 16C-16D of IAS 32. [Refer: Financial instruments, class [member]; Financial assets; Derivatives [member]]

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The amount of assets less the amount of liabilities.

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The amount of trade payables and other payables. [Refer: Trade payables; Other payables]

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The amount of trade receivables and other receivables. [Refer: Trade receivables; Other receivables]

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