Equity - AOCI components (Details) - EUR (€) € in Millions	Jun. 30, 2020	Dec. 31, 2019
Equity [abstract]
OTHER ACCUMULATED COMPREHENSIVE INCOME	€ (30,637)	€ (24,168)
ITEMS NOT RECLASSIFIED TO PROFIT OR LOSS	(5,010)	(4,288)
Actuarial gains or losses on defined benefit pension plans	(4,756)	(4,764)
Non-current assets held for sale	0	0
Share in other income and expenses recognised in investments, joint ventures and associates	(6)	1
Other valuation adjustments	0	0
Changes in the fair value of equity instruments measured at fair value with changes in other comprehensive income	(257)	514
Inefficacy of fair value hedges of equity instruments measured at fair value with changes in other comprehensive income	0	0
Changes in the fair value of equity instruments measured at fair value with changes in other comprehensive income (hedged item)	166	44
Changes in the fair value of equity instruments measured at fair value with changes in other comprehensive income (hedging instrument)	(166)	(44)
Changes in the fair value of financial liabilities at fair value through profit or loss attributable to changes in credit risk	9	(39)
ITEMS THAT MAY BE RECLASSIFIED TO PROFIT OR LOSS:	(25,627)	(19,880)
Hedge of net investments in foreign operations (effective portion)	(2,940)	(5,464)
Exchange differences	(25,450)	(16,701)
Hedging derivatives (effective portion)	846	300
Changes in the fair value of debt instruments measured at fair value with changes in other comprehensive income	2,465	2,321
Hedging instruments (items not designated)	0	0
Non-current assets held for sale	0	0
Share in other income and expenses recognised in investments, joint ventures and associates	€ (548)	€ (336)

No definition available.

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- Definition

A component of equity representing the accumulated portion of gain (loss) on a hedging instrument that is determined to be an effective hedge for cash flow hedges. [Refer: Cash flow hedges [member]]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2019-01-01
-Paragraph 78
-Subparagraph e
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 9
-IssueDate 2019-01-01
-Paragraph 6.5.11
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=9&code=ifrs-tx-2019-en-r&anchor=para_6.5.11&doctype=Standard
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- Definition

A component of equity representing the accumulated change in fair value of financial liabilities attributable to change in the credit risk of the liabilities. [Refer: Credit risk [member]; Financial liabilities]

+ References

+ Details

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- Definition

A component of equity representing exchange differences on translation of financial statements of foreign operations recognised in other comprehensive income and accumulated in equity. [Refer: Other comprehensive income]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 21
-IssueDate 2019-01-01
-Paragraph 52
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=21&code=ifrs-tx-2019-en-r&anchor=para_52_b&doctype=Standard
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- Definition

A component of equity representing accumulated gains and losses from investments in equity instruments that the entity has designated at fair value through other comprehensive income.

+ References

+ Details

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- Definition

A component of equity representing the reserve of gains and losses on financial assets measured at fair value through other comprehensive income. [Refer: Financial assets measured at fair value through other comprehensive income; Other comprehensive income]

+ References

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- Definition

A component of equity representing the accumulated gains and losses on hedging instruments that hedge investments in equity instruments that the entity has designated at fair value through other comprehensive income.

+ References

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- Definition

A component of equity representing the accumulated remeasurements of defined benefit plans. [Refer: Defined benefit plans [member]]

+ References

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- Definition

The amount attributable to parent of accumulated items of income and expense (including reclassification adjustments) that are not recognized in profit or loss as required or permitted by other IFRSs.

+ References

No definition available.

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The portion of other recognized income and expense of investments in subsidiaries, joint ventures and associated entities that is recognised in other comprehensive income and accumulated in equity.

+ References

No definition available.

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The portion of The portion of other recognized income and expense of investments in subsidiaries, joint ventures and associated entities that is recognised in other comprehensive income and may be reclassified to profit or loss.

+ References

No definition available.

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- Definition

Hedge Ineffectiveness Measured At Fair Value Through Other Comprehensive Income

+ References

No definition available.

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Other Reserves, Non-Current Assets Held-For-Sale That May Be Reclassified To Profit Or Loss, Net Of Tax

+ References

No definition available.

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Other Reserves Noncurrent Assets Held For Sale Not Reclassified To Profit Or Loss

+ References

No definition available.

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- Definition

Amount of other reserves not reclassified to profit or loss that is attributable to parent.

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No definition available.

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- Definition

Other Reserves, Other Comprehensive Income, Before Tax, Gains (Losses) On Hedged Instrument

+ References

No definition available.

+ Details

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Other Reserves, Other Comprehensive Income, Before Tax, Gains (Losses) On Hedged Item

+ References

No definition available.

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Other Reserves, Other Comprehensive Income, Before Tax, Hedging Instruments Not Designated

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No definition available.

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Amount of other reserves that may be reclassified to profit or loss that is attributable to parent.

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Other Valuation Adjustments, Not Reclassified To Profit Or Loss, Net Of Tax

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No definition available.

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