Equity - Cash Flow Disclosures (Details) - EUR (€) € in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Entity Information [Line Items]
Net cash flow provided by operating activities	€ 10,994	€ 11,649	€ 11,763
Net cash flow used in investing activities	(5,223)	(4,286)	(5,327)
Net cash flow used in financing activities	(4,672)	(7,186)	(7,925)
Telefónica Brazil
Entity Information [Line Items]
Net cash flow provided by operating activities	3,644	3,710	3,678
Net cash flow used in investing activities	(1,529)	(1,477)	(2,741)
Net cash flow used in financing activities	(1,557)	(1,709)	(1,674)
Telefónica Germany
Entity Information [Line Items]
Net cash flow provided by operating activities	2,774	2,684	2,732
Net cash flow used in investing activities	(1,334)	(1,337)	(1,608)
Net cash flow used in financing activities	(1,586)	(1,498)	(1,339)
Colombia Telecomunicaciones
Entity Information [Line Items]
Net cash flow provided by operating activities	219	206	180
Net cash flow used in investing activities	(101)	(144)	30
Net cash flow used in financing activities	€ (58)	€ (80)	€ (225)

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The cash flows from (used in) financing activities, which are activities that result in changes in the size and composition of the contributed equity and borrowings of the entity, from continuing and discontinued operations.

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The cash flows from (used in) investing activities, which are the acquisition and disposal of long-term assets and other investments not included in cash equivalents, from continuing and discontinued operations.

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The cash flows from (used in) operating activities, which are the principal revenue-producing activities of the entity and other activities that are not investing or financing activities, from continuing and discontinued operations. [Refer: Revenue]

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