Financial Risk Management Objectives and Policies - Exposures to Foreign Currency (Detail) ¥ in Thousands, $ in Thousands	Dec. 31, 2018 USD ($)	Dec. 31, 2018 CNY (¥)	Dec. 31, 2017 CNY (¥)
Disclosure of nature and extent of risks arising from financial instruments [line items]
Cash and bank balances	$ 916,058	¥ 6,128,522	¥ 6,029,207
Financial liabilities	(1,367,096)	(9,146,000)	(9,059,407)
Trade and other payables	(1,074,893)	(7,191,134)	(7,507,031)
Foreign currency risk [Member] \| Singapore dollar [member]
Disclosure of nature and extent of risks arising from financial instruments [line items]
Quoted equity securities		21,876	24,714
Trade and other receivables		693	725
Cash and bank balances		220,268	418,875
Financial liabilities		(15,126)	(14,715)
Trade and other payables		(13,952)	(13,748)
Net assets/(liabilities)	31,952	213,759	415,851
Foreign currency risk [Member] \| Euro [Member]
Disclosure of nature and extent of risks arising from financial instruments [line items]
Trade and other receivables		25,827
Cash and bank balances		1,166	1,486
Trade and other payables		(17,452)	(10,857)
Net assets/(liabilities)	1,426	9,541	(9,371)
Foreign currency risk [Member] \| USD [member]
Disclosure of nature and extent of risks arising from financial instruments [line items]
Trade and other receivables		12,149	34,727
Cash and bank balances		28,518	16,068
Financial liabilities		(501,014)
Trade and other payables		(7,060)	(5,574)
Net assets/(liabilities)	(69,865)	(467,407)	45,221
Foreign currency risk [Member] \| Renminbi [member]
Disclosure of nature and extent of risks arising from financial instruments [line items]
Trade and other receivables		675	469
Cash and bank balances		31,662
Trade and other payables		(41,828)	(35,505)
Net assets/(liabilities)	(1,419)	(9,491)	(35,036)
Foreign currency risk [Member] \| Others [Member]
Disclosure of nature and extent of risks arising from financial instruments [line items]
Cash and bank balances		25	498
Trade and other payables			(24)
Net assets/(liabilities)	$ 4	¥ 25	¥ 474

Cash and bank balances.

No definition available.

Name:	cyd_CashAndBankBalances
Namespace Prefix:	cyd_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

Name:	cyd_CurrentFinancialAssetsAtFairValueThroughProfitOrLossClassifiedAsQuotedEquitySecurities
Namespace Prefix:	cyd_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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.

+ References

No definition available.

+ Details

Name:	ifrs-full_DisclosureOfNatureAndExtentOfRisksArisingFromFinancialInstrumentsLineItems
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

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]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2018-01-01
-Paragraph 25
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2018-03-01&anchor=para_25&doctype=Standard
-URIDate 2018-03-16

+ Details

Name:	ifrs-full_FinancialLiabilities
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The amount of assets less the amount of liabilities.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Name IFRS
-Number 1
-IssueDate 2018-01-01
-Paragraph IG63
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=1&date=2018-03-01&anchor=para_IG63&doctype=Implementation%20Guidance
-URIDate 2018-03-16

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2018-01-01
-Paragraph 112
-Subparagraph c
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_112_c&doctype=Standard
-URIDate 2018-03-16

+ Details

Name:	ifrs-full_NetAssetsLiabilities
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2018-01-01
-Paragraph 54
-Subparagraph k
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_54_k&doctype=Standard
-URIDate 2018-03-16

+ Details

Name:	ifrs-full_TradeAndOtherPayables
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2018-01-01
-Paragraph 54
-Subparagraph h
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_54_h&doctype=Standard
-URIDate 2018-03-16

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2018-01-01
-Paragraph 78
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_78_b&doctype=Standard
-URIDate 2018-03-16

+ Details

Name:	ifrs-full_TradeAndOtherReceivables
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	ifrs-full_TypesOfRisksAxis=ifrs-full_CurrencyRiskMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_CurrencyAxis=currency_SGD
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_CurrencyAxis=currency_EUR
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_CurrencyAxis=currency_USD
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_CurrencyAxis=currency_CNY
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_CurrencyAxis=cyd_OtherCurrenciesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: