Taxes - Summary of income tax reconciliation (Details) - EUR (€) € in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Taxes
Income/ loss (-) before tax	€ (29,209)	€ (115,507)	€ 54,246
Income tax debit / credit (-), calculated using the Belgian statutory tax rate on the accounting income / loss (-) before tax (theoretical)	(8,640)	(39,261)	18,438
Tax expenses / income (-) in statement of operations (effective)	50	198	235
Difference in tax expense / income to explain	8,690	39,458	(18,203)
Effect of tax rates in other jurisdictions	411	14	163
Effect of non taxable revenues	(11,558)	(11,277)	(27,399)
Effect of share based payment expenses without tax impact	7,530	5,317	3,531
Effect of consolidation eliminations without tax impact	382	102	2
Effect of non tax deductible expenses	945	404	856
Effect of recognition of previously non recognized deferred tax assets	(1,977)	(414)	(421)
Effect of change in tax rates		181
Effect of tax losses (utilized) reversed	(150)	(763)	(655)
Effect of non recognition of deferred tax assets	13,108	45,895	5,720
Total explanations	€ 8,690	€ 39,458	€ (18,203)

Represents the amount explained of the difference in tax expense (income) between the statutory and effective tax rate.

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- Definition

Represents the difference in tax expense (income) between statutory and effective tax rate.

+ References

No definition available.

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- Definition

Effect of share based payment expenses without tax impact

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- Definition

The amount that represents the difference between the tax expense (income) and the product of the accounting profit multiplied by the applicable tax rate(s) that relates to non recognition of deferred tax assets in determining taxable profit (tax loss). [Refer: Accounting profit]

+ References

No definition available.

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The amount that represents the difference between the tax expense (income) and the product of the accounting profit multiplied by the applicable tax rate(s) that relates to tax losses (utilized) reversed in determining taxable profit (tax loss). [Refer: Accounting profit]

+ References

No definition available.

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- Definition

The amount that represents the difference between the tax expense (income) and the product of the accounting profit multiplied by the applicable tax rate(s) that relates to the effect of consolidation entry without tax impact in determining taxable profit (tax loss). [Refer: Accounting profit]

+ References

No definition available.

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- Definition

The amount that represents the difference between the tax expense (income) and the product of the accounting profit multiplied by the applicable tax rate(s) that relates to recognition of previously non recognized deferred tax assets in determining taxable profit (tax loss). [Refer: Accounting profit]

+ References

No definition available.

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- Definition

The amount of profit (loss) for a period before deducting tax expense. [Refer: Profit (loss)]

+ References

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- Definition

The aggregate amount included in the determination of profit (loss) for the period in respect of current tax and deferred tax. [Refer: Current tax expense (income); Deferred tax expense (income)]

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- Definition

The amount that represents the difference between the tax expense (income) and the product of the accounting profit multiplied by the applicable tax rate(s) that relates to changes in the tax rate. [Refer: Accounting profit]

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- Definition

The amount that represents the difference between the tax expense (income) and the product of the accounting profit multiplied by the applicable tax rate(s) that relates to expenses not deductible in determining taxable profit (tax loss). [Refer: Accounting profit]

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The amount that represents the difference between the tax expense (income) and the product of the accounting profit multiplied by the applicable tax rate(s) that relates to foreign tax rates. [Refer: Accounting profit]

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The amount that represents the difference between the tax expense (income) and the product of the accounting profit multiplied by the applicable tax rate(s) that relates to revenues that are exempt from taxation. [Refer: Accounting profit]

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The product of the accounting profit multiplied by the applicable tax rate(s). [Refer: Accounting profit; Applicable tax rate]

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