XML 137 R87.htm IDEA: XBRL DOCUMENT
v3.19.3.a.u2

Deferred tax assets and liabilities - Additional information (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |  |
Unremitted earnings retained for reinvestment | $ 7,000,000,000 |  |
Temporary differences and unused tax losses for which no deferred tax assets were recognized | 9,000,000,000 | $ 9,000,000,000 |
Tax loss carryforwards capitalized | 521,000,000 | 146,000,000 |
Tax loss carryforwards expiring in five years | 33,000,000 |  |
Tax loss carryforwards expiring in more than five years | 488,000,000 |  |
Tax loss carryforwards expired in period | 0 | 0 | $ 0
Deferred tax expense (income) relating to tax rate changes or imposition of new taxes | 0 | $ 0 | (413,000,000)
Income statement [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |  |
Revaluation of deferred tax assets and liabilities and current income tax liabilities |  |  | 413,000,000
Equity statement [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |  |
Revaluation of deferred tax assets and liabilities and current income tax liabilities |  |  | $ 18,000,000
Switzerland [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |  |
Deferred tax expense (income) relating to tax rate changes or imposition of new taxes | $ 304,000,000 |  |

X
- Definition Deferred Tax Asset, Tax Loss Carryforwards Capitalized + References No definition available. + Details
Name: | alc_DeferredTaxAssetTaxLossCarryforwardsCapitalized
Namespace Prefix: | alc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Deferred Tax Asset, Tax Loss Carryforwards Expiring In Five Years + References No definition available. + Details
Name: | alc_DeferredTaxAssetTaxLossCarryforwardsExpiringInFiveYears
Namespace Prefix: | alc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Deferred Tax Asset, Tax Loss Carryforwards Expiring In More Than Five Years + References No definition available. + Details
Name: | alc_DeferredTaxAssetTaxLossCarryforwardsExpiringInMoreThanFiveYears
Namespace Prefix: | alc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Deferred Tax Assets (Liabilities), Change In Enacted Tax Rate, Revaluation Of Deferred Tax Assets And Liabilities And Current Income Tax Liabilities + References No definition available. + Details
Name: | alc_DeferredTaxAssetsLiabilitiesChangeInEnactedTaxRateRevaluationOfDeferredTaxAssetsAndLiabilitiesAndCurrentIncomeTaxLiabilities
Namespace Prefix: | alc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Income Taxes, Unremitted Earnings Retained For Reinvestment + References No definition available. + Details
Name: | alc_IncomeTaxesUnremittedEarningsRetainedForReinvestment
Namespace Prefix: | alc_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Tax Effect Of Tax Rate Change On Current And Deferred Tax Assets And Liabilities + References No definition available. + Details
Name: | alc_TaxEffectOfTaxRateChangeOnCurrentAndDeferredTaxAssetsAndLiabilities
Namespace Prefix: | alc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Unused Tax Losses Expired During Period + References No definition available. + Details
Name: | alc_UnusedTaxLossesExpiredDuringPeriod
Namespace Prefix: | alc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The amount of deductible temporary differences for which no deferred tax asset is recognised in the statement of financial position. [Refer: Temporary differences [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2019-01-01 -Paragraph 81 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=12&code=ifrs-tx-2019-en-r&anchor=para_81_e&doctype=Standard -URIDate 2019-03-27 + Details
Name: | ifrs-full_DeductibleTemporaryDifferencesForWhichNoDeferredTaxAssetIsRecognised
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | instant

X
- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table. + References No definition available. + Details
Name: | ifrs-full_DisclosureOfTemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsLineItems
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | alc_FinancialStatementLocationAxis=alc_IncomeStatementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | alc_FinancialStatementLocationAxis=alc_EquityStatementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_GeographicalAreasAxis=country_CH
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |