4. Stock Options (Details) - EUR (€) € / shares in Units, € in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Minimum
Weighted Average Exercise Price Outstanding, Beginning	€ 0.02	€ 0.02
Weighted Average Exercise Price Granted
Weighted Average Exercise Price Exercised
Weighted Average Exercise Price Expired/Forfeited
Weighted Average Exercise Price Outstanding, Ending	0.02	0.02
Maximum
Weighted Average Exercise Price Outstanding, Beginning	0.19	0.19
Weighted Average Exercise Price Granted
Weighted Average Exercise Price Exercised
Weighted Average Exercise Price Expired/Forfeited
Weighted Average Exercise Price Outstanding, Ending	€ 0.19	€ 0.19
Stock options
Number of Options Outstanding, Beginning	29,100,000	29,100,000
Number of Options Granted	0	0
Number of Options Exercised	0	0
Number of Options Expired/Forfeited	0	0
Number of Options Outstanding, Ending	29,100,000	29,100,000
Weighted Average Exercise Price Outstanding, Beginning	€ 0.0364	€ 0.0364
Weighted Average Exercise Price Granted	0.000	0.000
Weighted Average Exercise Price Exercised	0.000	0.000
Weighted Average Exercise Price Expired/Forfeited	0.000	0.000
Weighted Average Exercise Price Outstanding, Ending	€ 0.0364	€ 0.0364
Weighted Average Remaining Contractual Life Outstanding	4 years 9 months 22 days
Weighted Average Remaining Contractual Life Exercisable	4 years 8 months 19 days
Aggregate Intrinsic Value Outstanding, Ending	€ 809,400
Aggregate Intrinsic Value Exercisable	€ 762,066

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

+ References

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- Definition

Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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- Definition

Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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- Definition

Weighted average price at which option holders acquired shares when converting their stock options into shares.

+ References

No definition available.

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- Definition

Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

+ References

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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

+ References

No definition available.

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- Definition

Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Number of share options (or share units) exercised during the current period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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