XML 105 R97.htm IDEA: XBRL DOCUMENT v3.23.2

SHARE-BASED COMPENSATION - Narrative (Details) - EUR (€) € / shares in Units, € in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Share Based Payment Plans [line items]
Number of instruments other equity instruments vested		2,518,292
Expense from share-based payment transactions with employees		€ 10	€ 9
Antidilutive securities (in shares)	2,997,790
PSUs
Share Based Payment Plans [line items]
Vesting period		3 years
PSUs | Bottom of range
Share Based Payment Plans [line items]
Percentage of vesting multiplier		0.00%
PSUs | Top of range
Share Based Payment Plans [line items]
Percentage of vesting multiplier		20000.00%
RSUs
Share Based Payment Plans [line items]
Vesting period		3 years
Number of instruments other equity instruments vested		817,059
Share price at grant date (in EUR per share)		€ 15.23

X

- Definition

Instruments With Potential Future Dilutive Effect Not Included In Calculation Of Diluted Earnings Per Share

+ References

No definition available.

+ Details

Name:	cstm_InstrumentsWithPotentialFutureDilutiveEffectNotIncludedInCalculationOfDilutedEarningsPerShare
Namespace Prefix:	cstm_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Number of instruments other equity instruments vested.

+ References

No definition available.

+ Details

Name:	cstm_NumberOfInstrumentsOtherEquityInstrumentsVested
Namespace Prefix:	cstm_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Percentage of sharebased payments vesting multiplier.

+ References

No definition available.

+ Details

Name:	cstm_PercentageOfSharebasedPaymentsVestingMultiplier
Namespace Prefix:	cstm_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Share based Payment Arrangement Vesting Period

+ References

No definition available.

+ Details

Name:	cstm_ShareBasedPaymentArrangementVestingPeriod
Namespace Prefix:	cstm_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Share based payment plans.

+ References

No definition available.

+ Details

Name:	cstm_ShareBasedPaymentPlansLineItems
Namespace Prefix:	cstm_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Share price at granted date.

+ References

No definition available.

+ Details

Name:	cstm_SharePriceatGrantedDate
Namespace Prefix:	cstm_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	duration

X

- Definition

The amount of expense from share-based payment transactions with employees. [Refer: Expense from share-based payment transactions]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2022-03-24
-Paragraph 112
-Subparagraph c
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2022-en-r&anchor=para_112_c&doctype=Standard
-URIDate 2022-03-24

+ Details

Name:	ifrs-full_ExpenseFromSharebasedPaymentTransactionsWithEmployees
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Details

Name:	ifrs-full_TypesOfSharebasedPaymentArrangementsAxis=cstm_PerformanceShareUnitsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	ifrs-full_RangeAxis=ifrs-full_BottomOfRangeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	ifrs-full_RangeAxis=ifrs-full_TopOfRangeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	ifrs-full_TypesOfSharebasedPaymentArrangementsAxis=cstm_RestrictedStockUnitsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: