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PENSIONS AND OTHER POST-EMPLOYMENT BENEFIT OBLIGATIONS - Benefit Payments Expected to be Paid Either by Pension Funds or Directly to Beneficiaries (Details) € in Millions | 12 Months Ended
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Dec. 31, 2020 EUR (€)
Disclosure of employee benefits [Abstract] |
2021 | € 49
2022 | 48
2023 | 49
2024 | 53
2025 | 52
2026 to 2030 | € 275

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- Definition Disclosure of employee benefits + References No definition available. + Details
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- Definition Estimated future benefit payments Five Fiscal Years Thereafter + References No definition available. + Details
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- Definition Estimated future benefit payments next twelve months + References No definition available. + Details
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- Definition Estimated future benefit payments Year Five + References No definition available. + Details
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- Definition Estimated future benefit payments Year Four + References No definition available. + Details
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- Definition Estimated future benefit payments Year Three + References No definition available. + Details
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- Definition Estimated future benefit payments Year Two + References No definition available. + Details
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Namespace Prefix: | cstm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration