Acquisition, Consideration

No definition available.

Name:	alc_AcquisitionConsideration
Namespace Prefix:	alc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contingent Consideration, Maximum Amount

+ References

No definition available.

+ Details

Name:	alc_ContingentConsiderationMaximumAmount
Namespace Prefix:	alc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The acquisition-date fair value of equity interest in the acquiree held by the acquirer immediately before the acquisition date in a business combination achieved in stages. [Refer: Total for all business combinations [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 3
-IssueDate 2025-01-01
-Paragraph B64
-Subparagraph p
-Clause i
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=3&code=ifrs-tx-2025-en-r&anchor=para_B64_p_i&doctype=Appendix&subtype=B
-URIDate 2025-03-27

+ Details

Name:	ifrs-full_AcquisitiondateFairValueOfEquityInterestInAcquireeHeldByAcquirerImmediatelyBeforeAcquisitionDate
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fair value, at acquisition date, of the consideration transferred in a business combination. [Refer: Total for all business combinations [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 3
-IssueDate 2025-01-01
-Paragraph B64
-Subparagraph f
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=3&code=ifrs-tx-2025-en-r&anchor=para_B64_f&doctype=Appendix&subtype=B
-URIDate 2025-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 35
-Subparagraph e
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_35_e&doctype=Standard
-URIDate 2025-03-27

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 35
-Subparagraph e
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_35_e&doctype=Standard
-URIDate 2025-03-27

+ Details

Name:	ifrs-full_AcquisitiondateFairValueOfTotalConsiderationTransferred
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 3
-IssueDate 2025-01-01
-Paragraph B64
-Subparagraph m
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=3&code=ifrs-tx-2025-en-r&anchor=para_B64_m&doctype=Appendix&subtype=B
-URIDate 2025-03-27

+ Details

Name:	ifrs-full_AcquisitionrelatedCostsForTransactionRecognisedSeparatelyFromAcquisitionOfAssetsAndAssumptionOfLiabilitiesInBusinessCombination
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The fair value, at acquisition date, of cash transferred as consideration in a business combination. [Refer: Total for all business combinations [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 3
-IssueDate 2025-01-01
-Paragraph B64
-Subparagraph f
-Clause i
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=3&code=ifrs-tx-2025-en-r&anchor=para_B64_f_i&doctype=Appendix&subtype=B
-URIDate 2025-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 35
-Subparagraph e
-Clause i
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_35_e_i&doctype=Standard
-URIDate 2025-03-27

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 35
-Subparagraph e
-Clause i
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_35_e_i&doctype=Standard
-URIDate 2025-03-27

+ Details

Name:	ifrs-full_CashTransferred
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The amount of consideration paid or received in respect of both obtaining and losing control of subsidiaries or other businesses. [Refer: Total for all subsidiaries [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 7
-IssueDate 2025-01-01
-Paragraph 40
-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=7&code=ifrs-tx-2025-en-r&anchor=para_40_a&doctype=Standard
-URIDate 2025-03-27

+ Details

Name:	ifrs-full_ConsiderationPaidReceived
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

+ References

No definition available.

+ Details

Name:	ifrs-full_DisclosureOfBusinessCombinationsLineItems
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The gain (loss) recognised as result of remeasuring to fair value the equity interest in the acquiree held by the acquirer before the business combination. [Refer: Total for all business combinations [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 3
-IssueDate 2025-01-01
-Paragraph B64
-Subparagraph p
-Clause ii
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=3&code=ifrs-tx-2025-en-r&anchor=para_B64_p_ii&doctype=Appendix&subtype=B
-URIDate 2025-03-27

+ Details

Name:	ifrs-full_GainLossRecognisedAsResultOfRemeasuringToFairValueEquityInterestInAcquireeHeldByAcquirerBeforeBusinessCombination
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The amount of assets representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognised. [Refer: Total for all business combinations [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 36
-IssueDate 2025-01-01
-Paragraph 134
-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=36&code=ifrs-tx-2025-en-r&anchor=para_134_a&doctype=Standard
-URIDate 2025-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 36
-IssueDate 2025-01-01
-Paragraph 135
-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=36&code=ifrs-tx-2025-en-r&anchor=para_135_a&doctype=Standard
-URIDate 2025-03-27

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 3
-IssueDate 2025-01-01
-Paragraph B67
-Subparagraph d
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=3&code=ifrs-tx-2025-en-r&anchor=para_B67_d&doctype=Appendix&subtype=B
-URIDate 2025-03-27

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 254
-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_254_a&doctype=Standard
-URIDate 2025-03-27

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 255
-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_255_a&doctype=Standard
-URIDate 2025-03-27

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 254
-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_254_a&doctype=Standard
-URIDate 2025-03-27

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 255
-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_255_a&doctype=Standard
-URIDate 2025-03-27

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 37
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_37&doctype=Standard
-URIDate 2025-03-27

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 37
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_37&doctype=Standard
-URIDate 2025-03-27

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2027-01-01
-Name IAS
-Number 1
-IssueDate 2025-01-01
-Paragraph 54
-Subparagraph c
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2025-en-b&anchor=para_54_c&doctype=Standard
-URIDate 2025-03-27

+ Details

Name:	ifrs-full_Goodwill
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The fair value, at acquisition date, of other tangible or intangible assets (including a business or subsidiary of the acquirer) transferred as consideration in a business combination, that the entity does not separately disclose in the same note. [Refer: Intangible assets other than goodwill; Total for all business combinations [member]; Total for all subsidiaries [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 3
-IssueDate 2025-01-01
-Paragraph B64
-Subparagraph f
-Clause ii
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=3&code=ifrs-tx-2025-en-r&anchor=para_B64_f_ii&doctype=Appendix&subtype=B
-URIDate 2025-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 35
-Subparagraph e
-Clause ii
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_35_e_ii&doctype=Standard
-URIDate 2025-03-27

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 35
-Subparagraph e
-Clause ii
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_35_e_ii&doctype=Standard
-URIDate 2025-03-27

+ Details

Name:	ifrs-full_OtherTangibleOrIntangibleAssetsTransferred
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The percentage of voting equity interests acquired in a business combination. [Refer: Total for all business combinations [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 3
-IssueDate 2025-01-01
-Paragraph B64
-Subparagraph c
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=3&code=ifrs-tx-2025-en-r&anchor=para_B64_c&doctype=Appendix&subtype=B
-URIDate 2025-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 35
-Subparagraph c
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_35_c&doctype=Standard
-URIDate 2025-03-27

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 35
-Subparagraph c
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_35_c&doctype=Standard
-URIDate 2025-03-27

+ Details

Name:	ifrs-full_PercentageOfVotingEquityInterestsAcquired
Namespace Prefix:	ifrs-full_
Data Type:	dtr-2022:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The profit (loss) of the acquiree, since the acquisition date, included in the consolidated statement of comprehensive income. [Refer: Profit (loss)]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 3
-IssueDate 2025-01-01
-Paragraph B64
-Subparagraph q
-Clause i
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=3&code=ifrs-tx-2025-en-r&anchor=para_B64_q_i&doctype=Appendix&subtype=B
-URIDate 2025-03-27

+ Details

Name:	ifrs-full_ProfitLossOfAcquiree
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The proportion of ownership interest in a subsidiary attributable to the entity. [Refer: Total for all subsidiaries [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 27
-IssueDate 2025-01-01
-Paragraph 17
-Subparagraph b
-Clause iii
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=27&code=ifrs-tx-2025-en-r&anchor=para_17_b_iii&doctype=Standard
-URIDate 2025-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 27
-IssueDate 2025-01-01
-Paragraph 16
-Subparagraph b
-Clause iii
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=27&code=ifrs-tx-2025-en-r&anchor=para_16_b_iii&doctype=Standard
-URIDate 2025-03-27

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 12
-IssueDate 2025-01-01
-Paragraph 19B
-Subparagraph c
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=12&code=ifrs-tx-2025-en-r&anchor=para_19B_c&doctype=Standard
-URIDate 2025-03-27

+ Details

Name:	ifrs-full_ProportionOfOwnershipInterestInSubsidiary
Namespace Prefix:	ifrs-full_
Data Type:	dtr-2022:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The proportion of the voting rights in an associate held by the entity. [Refer: Total for all associates [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 27
-IssueDate 2025-01-01
-Paragraph 17
-Subparagraph b
-Clause iii
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=27&code=ifrs-tx-2025-en-r&anchor=para_17_b_iii&doctype=Standard
-URIDate 2025-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 27
-IssueDate 2025-01-01
-Paragraph 16
-Subparagraph b
-Clause iii
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=27&code=ifrs-tx-2025-en-r&anchor=para_16_b_iii&doctype=Standard
-URIDate 2025-03-27

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 12
-IssueDate 2025-01-01
-Paragraph 21
-Subparagraph a
-Clause iv
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=12&code=ifrs-tx-2025-en-r&anchor=para_21_a_iv&doctype=Standard
-URIDate 2025-03-27

+ Details

Name:	ifrs-full_ProportionOfVotingPowerHeldInAssociate
Namespace Prefix:	ifrs-full_
Data Type:	dtr-2022:percentItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	srt_CounterpartyNameAxis=alc_LENSARIncMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_SignificantInvestmentsInSubsidiariesAxis=alc_AurionBiotechIncMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_BusinessCombinationsAxis=alc_AurionBiotechIncMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_BusinessCombinationsAxis=alc_CylitePtyLtdMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Acquisitions - Additional Information (Details) - USD ($) $ in Millions				3 Months Ended		5 Months Ended	6 Months Ended
	Mar. 24, 2025	Mar. 23, 2025	Jan. 16, 2025	Jun. 30, 2025	Mar. 31, 2025	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Disclosure of detailed information about business combination [line items]
Investment ownership percentage							21.40%
Goodwill							$ 9,259		$ 9,256
Cash paid for the acquisition							$ 0	$ 568
LENSAR, Inc.
Disclosure of detailed information about business combination [line items]
Total consideration (up to)		$ 430
Aurion Biotech, Inc.
Disclosure of detailed information about business combination [line items]
Investment ownership percentage		40.30%
Ownership percentage in subsidiary	99.00%
Aurion Biotech, Inc.
Disclosure of detailed information about business combination [line items]
Percentage of outstanding shares acquired	58.70%
Total acquisition date fair value of consideration	$ 486
Previously-held commercialization rights in intangible assets	36
Cash paid at closing	522
Goodwill	175
Cash paid for the acquisition	496
Previously-held investment in associated company	334
Equity interest remeasurement fair value gain					$ 136
Direct acquisition cost	$ 2
Reduction in net income from acquired business				$ 17
Cylite Pty Ltd.
Disclosure of detailed information about business combination [line items]
Percentage of outstanding shares acquired			91.20%
Total acquisition date fair value of consideration									123
Cash paid at closing									78
Goodwill			$ 90						90
Cash paid for the acquisition			72
Contingent consideration, maximum			10
Previously-held investment in associated company			14						$ 14
Equity interest remeasurement fair value gain					$ 6
Direct acquisition cost			$ 1
Reduction in net income from acquired business						$ 8