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The fair value of financial instruments designated as hedging instruments. Hedging instruments are designated derivatives or (for a hedge of the risk of changes in foreign currency exchange rates only) designated non-derivative financial assets or non-derivative financial liabilities whose fair value or cash flows are expected to offset changes in the fair value or cash flows of a designated hedged item. [Refer: At fair value [member]; Derivatives [member]; Derivative financial assets; Derivative financial liabilities; Financial instruments, class [member]; Financial assets; Financial liabilities]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2021-01-01
-Name IFRS
-Number 7
-IssueDate 2018-01-01
-Paragraph 22
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-02&anchor=para_22_b&doctype=Standard&book=b
-URIDate 2018-03-16

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The gains (losses) on hedging instruments in fair value hedges. [Refer: Fair value hedges [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2021-01-01
-Name IFRS
-Number 7
-IssueDate 2018-01-01
-Paragraph 24
-Subparagraph a
-Clause i
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-02&anchor=para_24_a_i&doctype=Standard&book=b
-URIDate 2018-03-16

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The nominal or face amount of a financial instrument, used to calculate payments made on that instrument.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2018-01-01
-Paragraph 112
-Subparagraph c
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_112_c&doctype=Standard
-URIDate 2018-03-16

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It represents the derivative margin guarantees for cash and stand by letters of credit.

No definition available.

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It represents the amount of derivative contracts.

No definition available.

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It represents the liquid funds balance.

No definition available.

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It represents the percentage of fixed to fluctuations in interest rate.

No definition available.

Name:	ltm_PercentageOfFixedToFluctuationsInInterestRate
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It represents the undrawn committed credit line.

No definition available.

Name:	ltm_UndrawnCommittedCreditLine
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Data Type:	xbrli:monetaryItemType
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It represents the amount of vertical fall in cost of total fuel consumption.

No definition available.

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It represents the amount of vertical rise in cost of total fuel consumption.

No definition available.

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Name:	ifrs-full_TypesOfRisksAxis=ifrs-full_InterestRateRiskMember
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