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17. CONCESSION CONTRACT ASSETS (Details 1) - BRL (R$) R$ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018
Disclosure of assets recognised from costs to obtain or fulfil contracts with customers [line items] |  |
Balance at December 31, 2017 | R$ 1,729 |
Effects of IFRS 15 first-time adoption |  | 1,714
Additions | 1,167 | 893
Inflation adjustment | 34 | 88
Adjustment to expected contract cash flow from the concession | 15 | 13
Amounts received | (154) | (161)
Disposals | (6) |
Transfers to financial assets | (92) | (27)
Transfers to intangible assets | (685) | (750)
Transfers from PP&E |  | 1
Impairment | (3) |
Ending balance | 2,005 | 1,729
Energy Transmission Segment [Member] |  |
Disclosure of assets recognised from costs to obtain or fulfil contracts with customers [line items] |  |
Balance at December 31, 2017 | 1,129 |
Effects of IFRS 15 first-time adoption |  | 1,092
Additions | 221 | 96
Inflation adjustment | 34 | 88
Adjustment to expected contract cash flow from the concession | 15 | 13
Amounts received | (154) | (161)
Disposals | (4) |
Transfers to financial assets | (44) |
Transfers from PP&E |  | 1
Ending balance | 1,197 | 1,129
Energy Distribution Segment [Member] |  |
Disclosure of assets recognised from costs to obtain or fulfil contracts with customers [line items] |  |
Balance at December 31, 2017 | 518 |
Effects of IFRS 15 first-time adoption |  | 532
Additions | 903 | 727
Transfers to financial assets | (48) | (27)
Transfers to intangible assets | (630) | (672)
Impairment | (3) | (42)
Ending balance | 740 | 518
Gas Segment [Member] |  |
Disclosure of assets recognised from costs to obtain or fulfil contracts with customers [line items] |  |
Balance at December 31, 2017 | 82 |
Effects of IFRS 15 first-time adoption |  | 90
Additions | 43 | 70
Disposals | (2) |
Transfers to intangible assets | (55) | (78)
Ending balance | R$ 68 | R$ 82

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- Definition The amount of additions to non-current assets other than financial instruments, deferred tax assets, net defined benefit assets and rights arising under insurance contracts. [Refer: Deferred tax assets; Financial instruments, class [member]; Non-current assets; Types of insurance contracts [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2019-01-01 -Paragraph 24 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2019-en-r&anchor=para_24_b&doctype=Standard -URIDate 2019-03-27 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2019-01-01 -Paragraph 28 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2019-en-r&anchor=para_28_e&doctype=Standard -URIDate 2019-03-27 + Details
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