Financial Liabilities - Maturity Analysis of Financial Liabilities (Details) - EUR (€) € in Millions	Dec. 31, 2022	Dec. 31, 2021
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Loans and other payables	€ 4,544	€ 4,693
Telefónica, S.A.
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Debentures and bonds	31,268
Promissory notes & commercial paper	899
Total Issues	32,167
Loans and other payables	4,544
Derivative instruments (Note 19)	2,368
Total	39,079	€ 42,295
Telefónica, S.A. \| 2023
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Debentures and bonds	1,948
Promissory notes & commercial paper	544
Total Issues	2,492
Loans and other payables	1,184
Derivative instruments (Note 19)	344
Total	4,020
Telefónica, S.A. \| 2024
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Debentures and bonds	1,130
Promissory notes & commercial paper	127
Total Issues	1,257
Loans and other payables	673
Derivative instruments (Note 19)	80
Total	2,010
Telefónica, S.A. \| 2025
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Debentures and bonds	3,126
Promissory notes & commercial paper	54
Total Issues	3,180
Loans and other payables	572
Derivative instruments (Note 19)	65
Total	3,817
Telefónica, S.A. \| 2026
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Debentures and bonds	2,098
Promissory notes & commercial paper	12
Total Issues	2,110
Loans and other payables	202
Derivative instruments (Note 19)	109
Total	2,421
Telefónica, S.A. \| 2027
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Debentures and bonds	4,170
Promissory notes & commercial paper	3
Total Issues	4,173
Loans and other payables	376
Derivative instruments (Note 19)	520
Total	5,069
Telefónica, S.A. \| Subsequent years
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Debentures and bonds	18,796
Promissory notes & commercial paper	159
Total Issues	18,955
Loans and other payables	1,537
Derivative instruments (Note 19)	1,250
Total	21,742
Telefónica, S.A. \| Non-current total
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Debentures and bonds	29,320
Promissory notes & commercial paper	355
Total Issues	29,675
Loans and other payables	3,360
Derivative instruments (Note 19)	2,024
Total	€ 35,059

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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