Provisions - Main Actuarial Assumptions Used in Valuing Defined Benefit Plans (Details) - Telefónica Spain - Foreign defined benefit plans	Dec. 31, 2017	Dec. 31, 2016
Survival
Disclosure of defined benefit plans [line items]
Discount rate	1.45%	1.26%
Survival \| Minimum
Disclosure of defined benefit plans [line items]
Expected rate of salary increase	0.00%	0.00%
Survival \| Maximum
Disclosure of defined benefit plans [line items]
Expected rate of salary increase	0.50%	0.50%
ITP
Disclosure of defined benefit plans [line items]
Discount rate	1.37%	1.16%

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 [member]]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 19
-IssueDate 2017-01-01
-Paragraph 144
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2017-03-01&anchor=para_144&doctype=Standard
-URIDate 2017-03-09

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- Definition

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

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- Definition

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

+ References

No definition available.

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