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

Cash Receipts (Payments) From Futures Contracts, Forward Contracts, Option Contracts And Swap Contracts

No definition available.

Name:	ats_CashReceiptsPaymentsFromFuturesContractsForwardContractsOptionContractsAndSwapContracts
Namespace Prefix:	ats_
Data Type:	xbrli:monetaryItemType
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Derivatives, Interest Rate, Fixed

No definition available.

Name:	ats_DerivativesInterestRateFixed
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Balance Type:	na
Period Type:	instant

Derivatives, Interest Rate, Paid

No definition available.

Name:	ats_DerivativesInterestRatePaid
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Balance Type:	na
Period Type:	instant

Derivatives, Interest Rate, Received

No definition available.

Name:	ats_DerivativesInterestRateReceived
Namespace Prefix:	ats_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

Other Non-Current Miscellaneous Assets

No definition available.

Name:	ats_OtherNonCurrentMiscellaneousAssets
Namespace Prefix:	ats_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

The cash outflow for futures contracts, forward contracts, option contracts and swap contracts except when the contracts are held for dealing or trading purposes or the payments are classified as financing activities.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Name IAS
-Number 7
-IssueDate 2024-01-01
-Paragraph 16
-Subparagraph g
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=7&code=ifrs-tx-2024-en-r&anchor=para_16_g&doctype=Standard
-URIDate 2024-03-27

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- References

No definition available.

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Data Type:	xbrli:stringItemType
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Period Type:	duration

- References

No definition available.

Name:	ifrs-full_MiscellaneousNoncurrentLiabilitiesAbstract
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
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The amount of non-current derivative financial assets. [Refer: Derivative financial assets]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2024-01-01
-Paragraph 55
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_55&doctype=Standard
-URIDate 2024-03-27

Name:	ifrs-full_NoncurrentDerivativeFinancialAssets
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

The amount of non-current derivative financial liabilities. [Refer: Derivative financial liabilities]

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

The amount of non-current investments other than investments accounted for using the equity method. [Refer: Investments accounted for using equity method; Non-current assets; Investments other than investments accounted for using equity method]

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

The nominal or face amount of a financial instrument, used to calculate payments made on that instrument.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2024-01-01
-Paragraph 112
-Subparagraph c
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_112_c&doctype=Standard
-URIDate 2024-03-27

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The amount of non-current assets that the entity does not separately disclose in the same statement or note. [Refer: Non-current assets]

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

The amount of non-current liabilities that the entity does not separately disclose in the same statement or note. [Refer: Non-current liabilities]

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
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Data Type:	na
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Name:	ifrs-full_ClassesOfFinancialLiabilitiesAxis=ats_CrossCurrencyInterestRateSwapInstrumentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	ifrs-full_ClassesOfFinancialLiabilitiesAxis=ats_VariableFixedInterestRateSwapInstrumentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	ifrs-full_ClassesOfFinancialLiabilitiesAxis=ats_ForwardForeignExchangeContractsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	ifrs-full_ClassesOfFinancialAssetsAxis=ats_CrossCurrencyInterestRateSwapInstrumentMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	ifrs-full_TypesOfHedgesAxis=ats_ForeignExchangeRiskMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	ifrs-full_BorrowingsByNameAxis=ats_SeniorNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	ats_DerivativeStatusAxis=ats_SettledMember
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Data Type:	na
Balance Type:
Period Type:

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	ats_DerivativeStatusAxis=ats_EnteredIntoMember
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Data Type:	na
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