The discount rate used as the significant actuarial assumption to determine the present value of a defined benefit obligation. [Refer: Defined benefit obligation, at present value; Actuarial assumptions [domain]]

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Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

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The amount of expense relating to restructuring. Restructuring is a programme that is planned and controlled by management and materially changes either the scope of a business undertaken by an entity or the manner in which that business is conducted. Such programmes include: (a) the sale or termination of a line of business; (b) closure of business locations in a country or region or the relocation of activities from one country or region to another; (c) changes in management structure; and (d) fundamental reorganisations that have a material effect on the nature and focus of the entity's operations.

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The amount of current provision for restructuring. [Refer: Restructuring provision]

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The weighted average duration of a defined benefit obligation. [Refer: Weighted average [member]]

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Restructuring Plan, Minimum Age Of Employees

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Provisions - Employee Benefits Narrative (Details) € in Millions			12 Months Ended
	Dec. 28, 2023 worker model	Dec. 28, 2023 yr worker	Dec. 31, 2024 EUR (€)	Dec. 31, 2023 EUR (€)
Disclosure of other provisions [line items]
Restructuring provision			€ 104	€ 1,538
Number of workers \| worker	3,420	3,420
Minimum age of employees (in years)	56	56
Minimum seniority of employees (in years) \| yr		15
Expense of restructuring activities				1,320
Telefónica Spain
Disclosure of other provisions [line items]
Expense of restructuring activities			1,248	1,299
Current restructuring provision			231	107
Telefónica Spain \| Operating segments
Disclosure of other provisions [line items]
Restructuring provision			€ 27	€ 1,320
Restructuring provision \| Telefónica Spain
Disclosure of other provisions [line items]
Discount rate			2.76%
Average duration of plans			3 years 2 months 8 days