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PENSIONS AND OTHER POST-EMPLOYMENT BENEFIT OBLIGATIONS - Net Defined Benefit Obligations by Country (Details) € in Millions, $ in Millions | Jun. 30, 2021 EUR (€) | Dec. 31, 2020 EUR (€) | Dec. 31, 2020 USD ($)
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Disclosure of net defined benefit liability (asset) [line items] |  |  |
Defined benefit obligations | € 1,085 | € 1,122 |
Plan assets | (504) | (458) |
Net defined benefit liability | 581 | 664 | $ 664
France |  |  |
Disclosure of net defined benefit liability (asset) [line items] |  |  |
Defined benefit obligations | 163 | 168 |
Plan assets | (5) | (5) |
Net defined benefit liability | 158 | 163 |
Germany |  |  |
Disclosure of net defined benefit liability (asset) [line items] |  |  |
Defined benefit obligations | 134 | 143 |
Plan assets | (2) | (1) |
Net defined benefit liability | 132 | 142 |
Switzerland |  |  |
Disclosure of net defined benefit liability (asset) [line items] |  |  |
Defined benefit obligations | 295 | 310 |
Plan assets | (248) | (223) |
Net defined benefit liability | 47 | 87 |
United States |  |  |
Disclosure of net defined benefit liability (asset) [line items] |  |  |
Defined benefit obligations | 492 | 500 |
Plan assets | (249) | (229) |
Net defined benefit liability | 243 | 271 |
Other |  |  |
Disclosure of net defined benefit liability (asset) [line items] |  |  |
Defined benefit obligations | 1 | 1 |
Plan assets | 0 | 0 |
Net defined benefit liability | € 1 | € 1 |

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- Definition Defined benefit obligation. + References No definition available. + Details
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- 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
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- Definition The amount of deficit or surplus in a defined benefit plan, adjusted for any effect of limiting a net defined benefit asset to the asset ceiling. [Refer: Defined benefit plans [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2020-01-01 -Paragraph 140 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2020-en-r&anchor=para_140_a&doctype=Standard -URIDate 2020-01-01 + Details
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- Definition The fair value of defined benefit plan assets. Plan assets comprise assets held by a long-term employee benefit fund and qualifying insurance policies. [Refer: At fair value [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 19 -IssueDate 2020-01-01 -Paragraph 57 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2020-en-r&anchor=para_57_a&doctype=Standard -URIDate 2020-01-01 + Details
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- Details
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