v3.8.0.1

Contracted concessional assets (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016
Movements of Contracted Concessional Assets [Abstract] |  |
Contracted concessional financial assets | $ 1,169,216 | $ 1,100,243
Total, beginning of period | 8,924,272 |
Total, end of period | 9,084,270 | 8,924,272
Cost [Member] |  |
Movements of Contracted Concessional Assets [Abstract] |  |
Total, beginning of period | 10,067,596 | 10,126,023
Additions | 15,426 | 6,346
Subtractions | (42,500) |
Translation differences | 593,247 | (68,199)
Change in the scope of the consolidated financial statements |  | 5,876
Reclassification and other movements |  | (2,450)
Total, end of period | 10,633,769 | 10,067,596
Accumulated Amortization [Member] |  |
Movements of Contracted Concessional Assets [Abstract] |  |
Total, beginning of period | (1,143,324) | (825,126)
Additions | (309,846) | (332,925)
Translation differences | (96,329) | 17,108
Change in the scope of the consolidated financial statements |  | (2,381)
Total, end of period | (1,549,499) | (1,143,324)
Contracted Concessional Assets [Member] |  |
Movements of Contracted Concessional Assets [Abstract] |  |
Contracted concessional financial assets | 936,004 | $ 928,720
Impairment loss | $ 0 |
Palmatir and Cadonal [Member] |  |
Movements of Contracted Concessional Assets [Abstract] |  |
Assumed percentage decrease in generation |  | 5.00%
Assumed percentage increase in discount rate |  | 0.50%
Palmatir and Cadonal [Member] | Bottom of Range [Member] |  |
Movements of Contracted Concessional Assets [Abstract] |  |
Discount rate |  | 6.70%
Palmatir and Cadonal [Member] | Top of Range [Member] |  |
Movements of Contracted Concessional Assets [Abstract] |  |
Discount rate |  | 7.00%
Cadonal [Member] |  |
Movements of Contracted Concessional Assets [Abstract] |  |
Impairment loss |  | $ 17,299
Recoverable amount of impairment loss |  | 91,795
Additional impairment loss that could be recognised due to assumed percentage decrease in generation |  | 5,000
Additional impairment loss that could be recognised due to assumed increase in discount rate |  | 3,000
Palmatir [Member] |  |
Movements of Contracted Concessional Assets [Abstract] |  |
Impairment loss |  | 3,101
Recoverable amount of impairment loss |  | 123,912
Additional impairment loss that could be recognised due to assumed percentage decrease in generation |  | 7,000
Additional impairment loss that could be recognised due to assumed increase in discount rate |  | $ 4,000
Solana [Member] |  |
Movements of Contracted Concessional Assets [Abstract] |  |
Assumed percentage decrease in generation | 5.00% | 5.00%
Additional impairment loss that could be recognised due to assumed percentage decrease in generation |  | $ 40,000
Assumed percentage increase in discount rate | 0.50% | 0.50%
Additional impairment loss that could be recognised due to assumed increase in discount rate |  | $ 30,000
Percentage recoverable amount exceeds carrying amount | 7.00% | 3.00%
Solana [Member] | Bottom of Range [Member] |  |
Movements of Contracted Concessional Assets [Abstract] |  |
Discount rate | 4.70% | 4.10%
Solana [Member] | Top of Range [Member] |  |
Movements of Contracted Concessional Assets [Abstract] |  |
Discount rate | 5.00% | 5.10%

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