XML 81 R74.htm IDEA: XBRL DOCUMENT v3.10.0.1

Trade Receivables and Other - Summary of Contract Assets (Detail) - EUR (€) € in Millions	Jun. 30, 2018	Jan. 01, 2018
Disclosure of disaggregation of revenue from contracts with customers [line items]
Non-current	€ 36	€ 32
Current	1	1
Unbilled Tooling Costs [member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Non-current	33	28
Other Cost [member]
Disclosure of disaggregation of revenue from contracts with customers [line items]
Non-current	3	4
Current	€ 1	€ 1

X

- Definition

The amount of current contract assets. [Refer: Contract assets]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2018-01-01
-Name IFRS
-Number 15
-IssueDate 2017-01-01
-Paragraph 105
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=15&date=2017-03-01&anchor=para_105&doctype=Standard
-URIDate 2017-03-09

+ Details

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

X

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

X

- Definition

The amount of non-current contract assets. [Refer: Contract assets]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2018-01-01
-Name IFRS
-Number 15
-IssueDate 2017-01-01
-Paragraph 105
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=15&date=2017-03-01&anchor=para_105&doctype=Standard
-URIDate 2017-03-09

+ Details

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

X

- Details

Name:	ifrs-full_CategoriesOfAssetsRecognisedFromCostsToObtainOrFulfilContractsWithCustomersAxis=cstm_UnbilledToolingCostsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	ifrs-full_CategoriesOfAssetsRecognisedFromCostsToObtainOrFulfilContractsWithCustomersAxis=cstm_OtherCostMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: