The spot exchange rate at the end of the reporting period. Exchange rate is the ratio of exchange for two currencies. Spot exchange rate is the exchange rate for immediate delivery.

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Derivative Financial Instruments and Risk Management Policies - Exchange Rate Risk (Details) € in Millions, VEF in Millions	12 Months Ended
	Dec. 31, 2017 EUR (€) VEB / $	Dec. 31, 2016 EUR (€) VEB / $	Dec. 31, 2017 VEF VEB / $	Dec. 31, 2015 VEB / $
Disclosure of detailed information about hedging instruments [line items]
Net debt held as a hedging instrument	€ 44,230
Foreign exchange gain (loss)	€ (419)	€ (694)
Foreign exchange rate \| VEB / $	36,115.280	673.762	36,115.280	198.699
Latin American currencies \| Foreign currency exchange risk \| Cash flow hedges
Disclosure of detailed information about hedging instruments [line items]
Net debt held as a hedging instrument	€ 4,689	€ 6,355
USD \| Foreign currency exchange risk \| Cash flow hedges
Disclosure of detailed information about hedging instruments [line items]
Net debt held as a hedging instrument	146	480
GBP \| Foreign currency exchange risk \| Cash flow hedges
Disclosure of detailed information about hedging instruments [line items]
Net debt held as a hedging instrument	€ 3,089	€ 2,828
Ratio of debt to OBIDA	1.97		1.97
VEB
Disclosure of detailed information about hedging instruments [line items]
Foreign exchange gain (loss)	€ (426)
VEB \| Foreign currency exchange risk \| Cash flow hedges
Disclosure of detailed information about hedging instruments [line items]
Net debt held as a hedging instrument	(170)		VEF 7,358,790
Increase in financial income due to the effect of monetary correction for inflation	€ 510