The description of the maximum term of options granted for a type of share-based payment arrangement that existed at any time during the period. An entity with substantially similar types of share-based payment arrangements may aggregate this information. [Refer: Share-based payment arrangements [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2017-01-01
-Paragraph 45
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2017-03-01&anchor=para_45_a&doctype=Standard
-URIDate 2017-03-09

+ Details

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

- Definition

The description of the vesting requirements for a type of share-based payment arrangement that existed at any time during the period. An entity with substantially similar types of share-based payment arrangements may aggregate this information. [Refer: Share-based payment arrangements [member]]

+ References

+ Details

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

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

- Definition

The number of share options outstanding in a share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2017-01-01
-Paragraph 45
-Subparagraph d
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2017-03-01&anchor=para_45_d&doctype=Standard
-URIDate 2017-03-09

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2017-01-01
-Paragraph 45
-Subparagraph b
-Clause i
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2017-03-01&anchor=para_45_b_i&doctype=Standard
-URIDate 2017-03-09

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2017-01-01
-Paragraph 45
-Subparagraph b
-Clause vi
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2017-03-01&anchor=para_45_b_vi&doctype=Standard
-URIDate 2017-03-09

+ Details

Name:	ifrs-full_NumberOfOutstandingShareOptions
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	instant

- Definition

The number of shares authorised.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2017-01-01
-Paragraph 79
-Subparagraph a
-Clause i
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_79_a_i&doctype=Standard
-URIDate 2017-03-09

+ Details

Name:	ifrs-full_NumberOfSharesAuthorised
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

The number of shares issued by the entity, for which full payment has been received.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2017-01-01
-Paragraph 79
-Subparagraph a
-Clause ii
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_79_a_ii&doctype=Standard
-URIDate 2017-03-09

+ Details

Name:	ifrs-full_NumberOfSharesIssuedAndFullyPaid
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of common stock allocated to investors to buy shares of a new issue of common stock before they are offered to the public. When stock is sold on a subscription basis, the issuer does not initially receive the total proceeds. In general, the issuer does not issue the shares to the investor until it receives the entire proceeds.

+ References

No definition available.

+ Details

Name:	ltm_CommonStockSharesSubscribedButUnissued1
Namespace Prefix:	ltm_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

The maximum number of shares (or other type of equity) originally subscribed, net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan.

+ References

No definition available.

+ Details

Name:	ltm_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesSubscription
Namespace Prefix:	ltm_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of share based payments effect on income recorded at fair value at the grant date.

+ References

No definition available.

+ Details

Name:	ltm_ShareBasedPaymentsEffectOnIncomeRecordedAtFairValueAtTheGrantDate
Namespace Prefix:	ltm_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	ifrs-full_TypesOfSharebasedPaymentArrangementsAxis=ltm_RestrictedStock1Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

- Details

Name:	ltm_CompensationPlanAxis=ltm_CompensationPlan2011Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_TypesOfSharebasedPaymentArrangementsAxis=ltm_StockOption1Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ltm_CompensationPlanAxis=ltm_CompensationPlan2013Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ltm_CompensationPlanAxis=ltm_CompensationPlan2016To2018Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ltm_CompensationPlanAxis=ltm_SubsidiariesCompensationPlansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

SHARE-BASED PAYMENTS (Details Narrative) $ in Thousands	12 Months Ended
SHARE-BASED PAYMENTS (Details Narrative) $ in Thousands	Dec. 31, 2017 USD ($) shares	Dec. 31, 2016 USD ($) shares	Dec. 31, 2015 shares	May 31, 2014 shares	Jun. 11, 2013 shares
Disclosure of terms and conditions of share-based payment arrangement [line items]
Number of shares authorised	608,374,525	608,374,525	551,847,819
Restricted Stock [Member] \| Multiplus S.A. [Member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Description of vesting requirements	(i) 1/3 (one third) after the 2nd year from the issue date; (ii) 1/3 (one third) after the 3rd year from the issue date; (iii) 1/3 (one third) after the 4th year from the issue date.
Number of ordinary restricted stock				91,103
Compensation Plan 2011 [Member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Number of shares subscription		4,800,000
Number of shares subscribed and fully paid		10,282
Shares pending of subscription and payment		4,789,718
Share based payments effect on income recorded at fair value at the grant date \| $		$ 2,989
Compensation Plan 2011 [Member] \| Stock Option [Member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Number of ordinary restricted stock			4,518,000
Compensation Plan 2013 [Member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Share based payments effect on income recorded at fair value at the grant date \| $
Number of shares authorised					1,500,000
Compensation Plan 2016-2018 [Member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Description of vesting requirements	A vesting period between October 2018 and March 2019.
Compensation Plan 2016-2018 [Member] \| Stock Option [Member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Number of ordinary restricted stock	2,932,896	4,719,720	4,719,720
Subsidiaries Compensation Plans [Member] \| Stock Option [Member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Description of maximum term of options granted	The options granted to the usual prizes are divided into three equal parts and employees may exercise one-third of their two, three and four, options respectively, as long as they keep being employees of the company. The agreed term of the options is seven years after the grant of the option. The first extraordinary granting was divided into two equal parts, and only half of the options may be exercised after three years and half after four years. The second extraordinary granting was also divided into two equal parts, which may be exercised after one and two years respectively.