Financial Liabilities - Maturity Analysis of Financial Liabilities (Details) - EUR (€) € in Millions	Dec. 31, 2023	Dec. 31, 2022
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Loans and other payables	€ 3,601	€ 4,544
Telefónica, S.A.
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Debentures and bonds	30,198
Promissory notes & commercial paper	1,369
Total Issues	31,567
Loans and other payables	3,601
Derivative instruments (Note 19)	1,893
Total	37,061	€ 39,079
Telefónica, S.A. \| 2024
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Debentures and bonds	1,565
Promissory notes & commercial paper	1,141
Total Issues	2,706
Loans and other payables	759
Derivative instruments (Note 19)	236
Total	3,701
Telefónica, S.A. \| 2025
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Debentures and bonds	3,133
Promissory notes & commercial paper	54
Total Issues	3,187
Loans and other payables	553
Derivative instruments (Note 19)	160
Total	3,900
Telefónica, S.A. \| 2026
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Debentures and bonds	2,072
Promissory notes & commercial paper	12
Total Issues	2,084
Loans and other payables	498
Derivative instruments (Note 19)	77
Total	2,659
Telefónica, S.A. \| 2027
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Debentures and bonds	3,911
Promissory notes & commercial paper	3
Total Issues	3,914
Loans and other payables	327
Derivative instruments (Note 19)	585
Total	4,826
Telefónica, S.A. \| 2028
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Debentures and bonds	2,110
Promissory notes & commercial paper	19
Total Issues	2,129
Loans and other payables	311
Derivative instruments (Note 19)	335
Total	2,775
Telefónica, S.A. \| Subsequent years
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Debentures and bonds	17,407
Promissory notes & commercial paper	140
Total Issues	17,547
Loans and other payables	1,153
Derivative instruments (Note 19)	500
Total	19,200
Telefónica, S.A. \| Non-current total
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Debentures and bonds	28,633
Promissory notes & commercial paper	228
Total Issues	28,861
Loans and other payables	2,842
Derivative instruments (Note 19)	1,657
Total	€ 33,360

The amount of contractual undiscounted cash flows in relation to bank borrowings. [Refer: Borrowings]

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The amount of contractual undiscounted cash flows in relation to bonds issued. [Refer: Bonds issued]

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The amount of outstanding funds that the entity is obligated to repay.

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The amount of contractual undiscounted cash flows in relation to derivative financial liabilities. [Refer: Derivative financial liabilities]

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No definition available.

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The amount of liabilities that are: (a) a contractual obligation: (i) to deliver cash or another financial asset to another entity; or (ii) to exchange financial assets or financial liabilities with another entity under conditions that are potentially unfavourable to the entity; or (b) a contract that will, or may be, settled in the entity’s own equity instruments and is: (i) a non-derivative for which the entity is, or may be, obliged to deliver a variable number of the entity’s own equity instruments; or (ii) a derivative that will, or may be, settled other than by the exchange of a fixed amount of cash or another financial asset for a fixed number of the entity’s own equity instruments. For this purpose, rights, options or warrants to acquire a fixed number of the entity’s own equity instruments for a fixed amount of any currency are equity instruments if the entity offers the rights, options or warrants pro rata to all of its existing owners of the same class of its own non-derivative equity instruments. Also, for those purposes the entity’s own equity instruments do not include puttable financial instruments that are classified as equity instruments in accordance with paragraphs 16A-16B of IAS 32, instruments that impose on the entity an obligation to deliver to another party a pro rata share of the net assets of the entity only on liquidation and are classified as equity instruments in accordance with paragraphs 16C-16D of IAS 32, or instruments that are contracts for the future receipt or delivery of the entity’s own equity instruments. As an exception, an instrument that meets the definition of a financial liability is classified as an equity instrument if it has all the features and meets the conditions in paragraphs 16A-16B or paragraphs 16C-16D of IAS 32. [Refer: Financial instruments, class [member]; Financial assets; Derivatives [member]]

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The amount of contractual undiscounted cash flows in relation to trade and other payables. [Refer: Trade and other payables]

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