XML 93 R85.htm IDEA: XBRL DOCUMENT v3.19.2

Trade Receivables and Other - Additional Information (Detail)	6 Months Ended
	Jun. 30, 2019 USD ($)	Jun. 30, 2019 EUR (€)	Jun. 30, 2018 EUR (€)	Dec. 31, 2018 EUR (€)
Disclosure of trade and other receivables [line items]
Allowance / (Reversal) of impairment		€ 100,000	€ (400,000)
Factored assets		631,000,000		€ 601,000,000
Factored assets, derecognized from Consolidated Statement of Financial Position		471,000,000		446,000,000
Factored assets, recognized in Consolidated Statement of Financial Position		160,000,000		155,000,000
Debt due factor		€ 0		€ 0
Factoring of receivables [member] | Muscle Shoals factoring facility [member]
Disclosure of trade and other receivables [line items]
Factoring maximum capacity | $	$ 375,000,000
Trade receivable factoring agreement maturity date	Jan. 24, 2020	Jan. 24, 2020
France [member] | Factoring of receivables [member]
Disclosure of trade and other receivables [line items]
Factoring maximum capacity		€ 235,000,000
Trade receivable factoring agreement maturity date	Oct. 29, 2021	Oct. 29, 2021
Germany Switzerland and Czech Republic [member] | Factoring of receivables [member]
Disclosure of trade and other receivables [line items]
Factoring maximum capacity		€ 150,000,000
Trade receivable factoring agreement maturity date	Oct. 29, 2021	Oct. 29, 2021
United States [member] | Factoring of receivables [member] | Constellium automotive [member]
Disclosure of trade and other receivables [line items]
Factoring maximum capacity | $	$ 33,000,000
Trade receivable factoring agreement maturity date	Dec. 11, 2019	Dec. 11, 2019

X

- Definition

Account Receivable Factoring Agreement Maturity Date

+ References

No definition available.

+ Details

Name:	cstm_AccountReceivableFactoringAgreementMaturityDate
Namespace Prefix:	cstm_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Derecognized factored assets.

+ References

No definition available.

+ Details

Name:	cstm_DerecognizedFactoredAssets
Namespace Prefix:	cstm_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Disclosure of trade and other receivables.

+ References

No definition available.

+ Details

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

X

- Definition

Due to Factor Related To Trade Account Receivables Sold

+ References

No definition available.

+ Details

Name:	cstm_DueToFactorRelatedToTradeAccountReceivablesSold
Namespace Prefix:	cstm_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

Factored assets derecognized and recognized in consolidated statement of financial position.

+ References

No definition available.

+ Details

Name:	cstm_FactoredAssetsDerecognizedAndRecognizedInConsolidatedStatementOfFinancialPosition
Namespace Prefix:	cstm_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Factored assets recognized in consolidated statement of financial position.

+ References

No definition available.

+ Details

Name:	cstm_FactoredAssetsRecognizedInConsolidatedStatementOfFinancialPosition
Namespace Prefix:	cstm_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

The maximum capacity according the factoring agreement.

+ References

No definition available.

+ Details

Name:	cstm_FactoringMaximumCapacity
Namespace Prefix:	cstm_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

The amount of impairment loss or reversal of impairment loss recognised in profit or loss for trade receivables. [Refer: Impairment loss recognised in profit or loss; Reversal of impairment loss recognised in profit or loss; Trade receivables]

+ References

Reference 1: 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_ImpairmentLossReversalOfImpairmentLossRecognisedInProfitOrLossTradeReceivables
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Details

Name:	ifrs-full_ContinuingInvolvementInDerecognisedFinancialAssetsByTypeOfTransferAxis=ifrs-full_FactoringOfReceivablesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	ifrs-full_BorrowingsByNameAxis=cstm_MuscleShoalsFactoringFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	ifrs-full_GeographicalAreasAxis=country_FR
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	ifrs-full_GeographicalAreasAxis=cstm_GermanySwitzerlandAndCzechRepublicMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	ifrs-full_GeographicalAreasAxis=country_US
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	ifrs-full_CategoriesOfRelatedPartiesAxis=cstm_ConstelliumAutomotiveMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: