Costs of geological and geophysical studies

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Disclosure Of Operating Expenses.

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Limit of shares to be granted in share-based payment arrangement

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Lock-up clause percentage

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The amount of minimum operating lease payment.

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The amount of net provisions for contingencies.

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Number of annual awards

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Percentage of shares that will be granted at the end of the vesting period, depending on an absolute parameter represented by an economic-financial objective measured as the Organic Free Cash Flow cumulated in the three-year reference period, compared to the equivalent cumulated value provided for in the first three years of the Strategic Plan approved by the Board of Directors in the year of award and kept unchanged during the performance period.

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Percentage of shares that will be granted at the end of the vesting period, depending on environmental sustainability and energy transition objective in a three-year period consisting of three absolute objectives.

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Percentage of shares that will be granted at the end of the vesting period, depending on the growth in the Net Present Value (NPV) of proved reserves benchmarked against the Peer Group

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Percentage of shares that will be granted at the end of the vesting period, depending on market condition, in terms of Total Shareholder Return (TSR) of the Group's share compared to the TSR of the FTSE Mib index of the Italian Stock Exchange Market, and to a group of company's competitors ("Peers Group") and the TSR of their corresponding stock exchange market.

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Percentage of shares that will be granted at the end of the vesting period, depending on a relative parameter represented by an industrial objective measured in terms of annual unit value ($/boe) of the Net Present Value of Proven Reserves (NPV) compared with the analogous value of each company in the Peer Group.

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Percentage of shares that will vest after vesting period

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The element represents about the share based payment arrangement lock-up clause term

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The element represents about the share based payment arrangement vesting term.

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Number of absolute objectives considered for determination of shares that will be granted at the end of the vesting period depending on environmental sustainability and energy transition objective.

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No definition available.

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Number of important projects, whose progress is considered for determination of shares that will be granted at the end of the vesting period depending on environmental sustainability and energy transition objective, under the circular economy absolute objective.

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No definition available.

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Percentage on a circular economy objective considered for determination of shares that will be granted at the end of the vesting period, depending on environmental sustainability and energy transition objective.

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No definition available.

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Percentage on energy transition objective considered for determination of shares that will be granted at the end of the vesting period, depending on environmental sustainability and energy transition objective.

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No definition available.

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Percentage to decarbonisation objective considered for determination of shares that will be granted at the end of the vesting period, depending on environmental sustainability and energy transition objective.

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No definition available.

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Weighted average fair value of awarded shares

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The amount of fees paid or payable to the entity's auditors.

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The expected volatility of the share price used to calculate the fair value of the share options granted. Expected volatility is a measure of the amount by which a price is expected to fluctuate during a period. The measure of volatility used in option pricing models is the annualised standard deviation of the continuously compounded rates of return on the share over a period of time.

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The amount of remuneration paid or payable to the entity's directors.

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The percentage of an expected dividend used to calculate the fair value of share options granted.

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The amount of expense from share-based payment transactions with employees.

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The number of other equity instruments (ie other than share options) granted in a share-based payment arrangement.

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The amount of post-employment benefit expense relating to defined contribution plans. Defined contribution plans are post-employment benefit plans under which an entity pays fixed contributions into a separate entity (a fund) and will have no legal or constructive obligation to pay further contributions if the fund does not hold sufficient assets to pay all employee benefits relating to employee service in the current and prior periods.

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The amount of expenditure directly attributable to research or development activities, recognised in profit or loss.

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The amount of expense arising from royalties.

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The amount of expense in relation to termination benefits. Termination benefits are employee benefits provided in exchange for the termination of an employee's employment as a result of either: (a) an entity's decision to terminate an employee's employment before the normal retirement date; or (b) an employee's decision to accept an offer of benefits in exchange for the termination of employment. [Refer: Employee benefits expense]

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The weighted average share price used as input to the option pricing model to calculate the fair value of share options granted. [Refer: Option pricing model [member]; Weighted average [member]]

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Costs - Additional information (Details) € / shares in Units, € in Thousands, shares in Millions	12 Months Ended
	Dec. 31, 2020 EUR (€) EquityInstruments item € / shares	Dec. 31, 2019 EUR (€) EquityInstruments € / shares	Dec. 31, 2018 EUR (€) € / shares	May 13, 2020 objector shares	Apr. 13, 2017 shares
Costs
Geological and geophysical costs of exploration activities	€ 196,000	€ 275,000	€ 287,000
Operating leases			872,000
Research and development costs	157,000	194,000	197,000
Royalty expense	673,000	1,183,000	1,043,000
Net additions for contingencies	349,000	858,000	1,120,000
Provisions for redundancy incentives expense	105,000	45,000	37,000
Defined contribution plans expense	€ 96,000	€ 99,000	€ 95,000
Number of annual awards \| item	3
Vesting period	3 years
Lock-up clause percentage	50.00%
Lock-up clause term	1 year
Number of other equity instruments granted in share-based payment arrangement	2,922,749	1,759,273	1,517,975.00
Weighted average fair value of awarded shares \| € / shares	€ 4.67	€ 9.88	€ 11.73
Weighted average share price at grant date \| € / shares		€ 13.714	€ 14.246
Expected dividend as percentage		6.10%	5.80%
Expected volatility		19.00%	20.00%
Expense from share-based payment transactions with employees	€ 7,000	€ 9,000	€ 5,000
Directors' remuneration expense	7,540	9,200	9,600
Statutory auditors remuneration expense	€ 571	613	604
Minimum
Costs
Percentage of shares that will vest after vesting period	0.00%
Weighted average share price at grant date \| € / shares	€ 5.885
Expected dividend as percentage	7.00%
Expected volatility	41.00%
Maximum
Costs
Percentage of shares that will vest after vesting period	180.00%
Weighted average share price at grant date \| € / shares	€ 8.303
Expected dividend as percentage	10.00%
Expected volatility	44.00%
Long-Term Monetary Incentive Plan 2017 - 2019
Costs
Percentage of shares that will be granted depending on market condition in terms of TSR					50.00%
Percentage of shares that will be granted depending on the growth in the Net Present Value (NPV) of proved reserves benchmarked against the Peer Group					50.00%
Long-Term Monetary Incentive Plan 2017 - 2019 \| Maximum
Costs
Limit of shares to be granted in share-based payment arrangement \| shares					11
Long-Term Monetary Incentive Plan 2020 - 2022
Costs
Percentage of shares that will be granted depending on market condition in terms of TSR				25.00%
Percentage of shares that will be granted depending on a relative parameter represented by an industrial objective				20.00%
Percentage of shares that will be granted depending on an absolute parameter represented by an economic-financial objective				20.00%
Percentage of shares that will be granted depending on environmental sustainability and energy transition objective				35.00%
Number of absolute objectives considered for determination of shares that will be granted depending on environmental sustainability and energy transition objective \| objector				3
Percentage of shares that will be granted depending on decarbonisation objective				15.00%
Percentage of shares that will be granted depending on energy transition objective				10.00%
Percentage of shares that will be granted depending on circular economy objective				10.00%
Number of important projects considered for determination of shares that will be granted depending on environmental sustainability and energy transition objective				3
Long-Term Monetary Incentive Plan 2020 - 2022 \| Maximum
Costs
Limit of shares to be granted in share-based payment arrangement \| shares				20
Provisions for litigations
Costs
Net additions for contingencies	€ 76,000	60,000	101,000
Environmental liabilities
Costs
Net additions for contingencies	€ (15,000)	€ 329,000	€ 266,000