XML 104 R97.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Income and Social Contribution Taxes - Summary of Changes in Deferred Income and Social Contribution Taxes (Detail) - BRL (R$) R$ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Disclosure of deferred income and social contribution taxes [Abstract] |  |  |
Beginning balance | R$ 1,215 | R$ 809 | R$ 635
Effects allocated to Statement of income | (198) | 141 | (12)
Effects allocated to Statement of comprehensive income | 133 | 265 | 191
Realized |  |  | (5)
Variations in deferred tax assets and liabilities | (14) |  |
Ending balance | R$ 1,136 | R$ 1,215 | R$ 809

X
- Definition The amount of tax expense or income relating to changes in deferred tax liabilities and deferred tax assets, recognised in profit or loss. [Refer: Deferred tax assets; Deferred tax expense (income); Deferred tax liabilities] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2017-01-01 -Paragraph 81 -Subparagraph g -Clause ii -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=12&date=2017-03-01&anchor=para_81_g_ii&doctype=Standard -URIDate 2017-03-09 + Details
Name: | ifrs-full_DeferredTaxExpenseIncomeRecognisedInProfitOrLoss
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount of deferred tax liabilities or assets. [Refer: Deferred tax liabilities; Deferred tax assets] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2017-01-01 -Paragraph 81 -Subparagraph g -Clause i -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=12&date=2017-03-01&anchor=para_81_g_i&doctype=Standard -URIDate 2017-03-09 + Details
Name: | ifrs-full_DeferredTaxLiabilityAsset
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The amount of income tax relating to amounts recognised in other comprehensive income. [Refer: Other comprehensive income] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2017-01-01 -Paragraph 81 -Subparagraph ab -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=12&date=2017-03-01&anchor=para_81_ab&doctype=Standard -URIDate 2017-03-09 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2017-01-01 -Paragraph 90 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_90&doctype=Standard -URIDate 2017-03-09 + Details
Name: | ifrs-full_IncomeTaxRelatingToComponentsOfOtherComprehensiveIncome
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- Definition The increase (decrease) in a deferred tax liability (asset). [Refer: Deferred tax liability (asset)] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 12 -IssueDate 2017-01-01 -Paragraph 81 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=12&date=2017-03-01&anchor=para_81&doctype=Standard -URIDate 2017-03-09 + Details
Name: | ifrs-full_IncreaseDecreaseInDeferredTaxLiabilityAsset
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Disclosure of deferred income and social contribution taxes. + References No definition available. + Details
Name: | xcmig_DisclosureOfDeferredIncomeAndSocialContributionTaxesAbstract
Namespace Prefix: | xcmig_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Increase (decrease) through realized, deferred tax liability (asset). + References No definition available. + Details
Name: | xcmig_IncreaseDecreaseThroughRealizedDeferredTaxLiabilityAsset
Namespace Prefix: | xcmig_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration