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Investments Accounted for Under Equity Method - Summary of Amounts Included in Financial Statements in Accordance with Group Accounting Principles (Detail) - EUR (€) € in Millions | 3 Months Ended | 6 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017 | Dec. 31, 2017 | Dec. 31, 2016
Current assets |  |  |  |  |  |
Cash and cash equivalents | € 166 |  | € 166 |  | € 269 | € 347
Trades receivables and other | 656 |  | 656 |  | 419 |
Inventories | 745 |  | 745 |  | 643 |
Other financial assets | 120 |  | 120 |  | 179 |
Non-current assets |  |  |  |  |  |
Property, plant and equipment | 1,545 |  | 1,545 |  | 1,517 |
Intangible assets | 68 |  | 68 |  | 68 |
Total Assets | 3,922 |  | 3,922 |  | 3,711 |
Current liabilities |  |  |  |  |  |
Trade payables and other | 1,096 |  | 1,096 |  | 930 |
Borrowings | 130 |  | 130 |  | 106 |
Non-current liabilities |  |  |  |  |  |
Borrowings | 2,054 |  | 2,054 |  | 2,021 |
Equity | (272) | € (517) | (272) | € (517) | (319) | € (570)
Total Equity and Liabilities | 3,922 |  | 3,922 |  | 3,711 |
Revenue | 1,474 | 1,382 | 2,860 | 2,710 |  |
Cost of sales | (1,303) | (1,232) | (2,556) | (2,420) |  |
Selling and administrative expenses | (60) | (62) | (118) | (127) |  |
Income (loss) from operations | 125 | 73 | 142 | 173 |  |
Finance costs | (37) | (41) | (73) | (96) |  |
Net income (loss) | 55 | 15 | 31 | 28 | (31) |
Finance income | 1 | 2 | 3 | 3 |  |
Constellium-UACJ ABS LLC [member] |  |  |  |  |  |
Current assets |  |  |  |  |  |
Cash and cash equivalents | 3 |  | 3 |  | 5 |
Trades receivables and other | 47 |  | 47 |  | 35 |
Inventories | 61 |  | 61 |  | 57 |
Non-current assets |  |  |  |  |  |
Property, plant and equipment | 164 |  | 164 |  | 161 |
Intangible assets | 1 |  | 1 |  | 1 |
Total Assets | 276 |  | 276 |  | 259 |
Current liabilities |  |  |  |  |  |
Trade payables and other | 55 |  | 55 |  | 34 |
Borrowings | 24 |  | 24 |  | 206 |
Non-current liabilities |  |  |  |  |  |
Borrowings | 251 |  | 251 |  | 47 |
Equity | (54) |  | (54) |  | (28) |
Total Equity and Liabilities | 276 |  | 276 |  | 259 |
Revenue | 72 | 33 | 118 | 56 |  |
Cost of sales | (82) | (40) | (141) | (69) |  |
Selling and administrative expenses | (2) | (2) | (5) | (5) |  |
Income (loss) from operations | (12) | (9) | (28) | (18) |  |
Finance costs | (5) | (4) | 4 | (7) |  |
Net income (loss) | (17) | (13) | (24) | (25) |  |
Group Companies and Constellium UACJ ABS LLC [member] |  |  |  |  |  |
Current assets |  |  |  |  |  |
Trades receivables and other | 25 |  | 25 |  | 15 |
Other financial assets | 76 |  | 76 |  | 83 |
Non-current assets |  |  |  |  |  |
Total Assets | 101 |  | 101 |  | € 98 |
Non-current liabilities |  |  |  |  |  |
Revenue | 48 | 10 | 78 | 21 |  |
Net income (loss) | 51 | 14 | 77 | 26 |  |
Fees and recharges | 1 | 2 | 2 | 2 |  |
Finance income | € 2 | € 2 | € (3) | € 3 |  |

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