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Summary of Significant Accounting Policies (Tables) | 12 Months Ended
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Dec. 31, 2018
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Opening Financial Position Reclassification (IFRS 15 Standard) | Upon adoption of IFRS 15, the Group made the following reclassifications in its opening financial position:
(in millions of Euros) |  | Carrying amount December 31, 2017 |  |  | Contract liabilities reclassification |  |  | Carrying amount January 1, 2018 |
Trade receivables and other |  |  | 467 |  |  |  | 18 |  |  |  | 485 |
Trade payables and other |  |  | (984 | ) |  |  | (41 | ) |  |  | (1,025 | )
Provisions |  |  | (153 | ) |  |  | 23 |  |  |  | (130 | )
Disclosure of Foreign Exchange Rates | The following table summarizes the main exchange rates used for the preparation of the Consolidated Financial Statements:
|  |  |  | Year ended December 31, 2018 |  |  | Year ended December 31, 2017 |  |  | Year ended December 31, 2016 |
Foreign exchange rate for 1 Euro |  |  |  | Average rate |  |  | Closing rate |  |  | Average rate |  |  | Closing rate |  |  | Average rate |  |  | Closing rate |
U.S. Dollars |  | USD |  |  | 1.1798 |  |  |  | 1.1450 |  |  |  | 1.1273 |  |  |  | 1.1993 |  |  |  | 1.1063 |  |  |  | 1.0541 |
Swiss Francs |  | CHF |  |  | 1.1546 |  |  |  | 1.1269 |  |  |  | 1.1103 |  |  |  | 1.1702 |  |  |  | 1.0901 |  |  |  | 1.0739 |
Czech Koruna |  | CZK |  |  | 25.6452 |  |  |  | 25.7240 |  |  |  | 26.3151 |  |  |  | 25.5349 |  |  |  | 27.0342 |  |  |  | 27.0210 |

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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 2018-01-01 -Section Disclosure -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=21&date=2018-03-01&anchor=sect_Disclosure&doctype=Standard -URIDate 2018-03-16 + 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 -Name IFRS -Number 7 -IssueDate 2018-01-01 -Paragraph 12B -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2018-03-01&anchor=para_12B&doctype=Standard -URIDate 2018-03-16 + Details
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