Account Receivable Factoring Agreement Maturity Date

No definition available.

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Namespace Prefix:	cstm_
Data Type:	xbrli:dateItemType
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Period Type:	duration

- Definition

Derecognized factored assets.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Disclosure of trade and other receivables.

+ References

No definition available.

+ Details

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- Definition

Due to Factor Related To Trade Account Receivables Sold

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Factored assets recognized in consolidated statement of financial position.

+ References

No definition available.

+ Details

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- Definition

The maximum capacity according the factoring agreement.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

The amount of receivables related to finance leases.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2018-01-01
-Paragraph 55
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_55&doctype=Standard
-URIDate 2018-03-16

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of reversal of impairment loss recognised in profit or loss for trade receivables. [Refer: 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

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Data Type:	xbrli:monetaryItemType
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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Trade Receivables and Other - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2018 EUR (€)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 EUR (€)
Disclosure of trade and other receivables [line items]
Reversal of impairment allowance	€ 1,100,000		€ 700,000
Factored assets	601,000,000		642,000,000
Factored assets, derecognized from Consolidated Statement of Financial Position	446,000,000		473,000,000
Factored assets, recognized in Consolidated Statement of Financial Position	155,000,000		169,000,000
Debt due factor	€ 0		0
Finance lease receivables			€ 12,000,000
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 \| $		$ 25,000,000
Trade receivable factoring agreement maturity date	Dec. 11, 2019	Dec. 11, 2019
United States [member] \| Factoring of receivables amendment [member] \| Constellium automotive [member]
Disclosure of trade and other receivables [line items]
Factoring maximum capacity \| $		$ 33,000,000