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Summary of Significant Accounting Policies (Tables) | 6 Months Ended
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Jun. 30, 2018
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Opening Balance Sheet Reclassification (IFRS 15 Standard) | Upon adoption of IFRS 15, the Group made the following reclassifications in its opening balance sheet:
(in millions of Euros) |  | Carrying amount December 31, 2017 |  |  | Contracts liabilities reclassification |  |  | Carrying amount January 1, 2018 |
Trade receivables and other |  |  | 467 |  |  |  | 16 |  |  |  | 483 |
Trade payables and other |  |  | (984 | ) |  |  | (39 | ) |  |  | (1,023 | )
Provisions |  |  | (153 | ) |  |  | 23 |  |  |  | (130 | )
Disclosure of Foreign Exchange Rates | The following table summarizes the principal exchange rates used for the preparation of the Unaudited Condensed Interim Consolidated Financial Statements of the Group:
Foreign exchange rate for 1 Euro |  | Six months ended June 30, 2018 Average rate |  |  | At June 30, 2018 Closing rate |  |  | Six months ended June 30, 2017 Average rate |  |  | At December 31, 2017 Closing rate |
U.S. Dollars |  | USD |  |  | 1.2097 |  |  |  | 1.1658 |  |  |  | 1.0824 |  |  |  | 1.1993 |
Swiss Francs |  | CHF |  |  | 1.1696 |  |  |  | 1.1569 |  |  |  | 1.0765 |  |  |  | 1.1702 |
Czech Koruna |  | CZK |  |  | 25.4992 |  |  |  | 26.0200 |  |  |  | 26.7809 |  |  |  | 25.5349 |

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- Definition The entire disclosure for the effect of changes in foreign exchange rates. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 21 -IssueDate 2017-01-01 -Section Disclosure -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=21&date=2017-03-01&anchor=sect_Disclosure&doctype=Standard -URIDate 2017-03-09 + Details
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- Definition The disclosure of information about the reclassification of financial assets. [Refer: Financial assets] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Note Effective 2018-01-01 -Name IFRS -Number 7 -IssueDate 2017-01-01 -Paragraph 12B -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-01&anchor=para_12B&doctype=Standard -URIDate 2017-03-09 + Details
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