The amount of annual base salary.

No definition available.

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Namespace Prefix:	lmca_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount of annual equity awards.

+ References

No definition available.

+ Details

Name:	lmca_AnnualEquityAwards
Namespace Prefix:	lmca_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount of the annual target cash performance bonus.

+ References

No definition available.

+ Details

Name:	lmca_AnnualTargetCashPerformanceBonus
Namespace Prefix:	lmca_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The allocation percentage for the Chief Executive Officer's compensation is the weighted average percentage that is based on the blended average of historical time allocation on a Liberty Media-wide and CEO basis.

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The allocation percentage for the Chief Executive Officer's compensation is the weighted average percentage that is based on the relative market capitalization.

+ References

No definition available.

+ Details

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Namespace Prefix:	lmca_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the length of time of an employment agreement.

+ References

No definition available.

+ Details

Name:	lmca_EmploymentAgreementTerm
Namespace Prefix:	lmca_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the number of equal tranches to grant the upfront awards.

+ References

No definition available.

+ Details

Name:	lmca_NumberOfEqualTranches
Namespace Prefix:	lmca_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Total number of exchanges of the Company's shares pursuant to the exchange agreement.

+ References

No definition available.

+ Details

Name:	lmca_NumberOfSharesExchanges
Namespace Prefix:	lmca_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

The allocation percentage under the officer compensation arrangement.

+ References

No definition available.

+ Details

Name:	lmca_OfficerCompensationArrangementAllocationPercentage
Namespace Prefix:	lmca_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of the one-time cash commitment bonus.

+ References

No definition available.

+ Details

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Namespace Prefix:	lmca_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the total fair value of options granted during the reporting period.

+ References

No definition available.

+ Details

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Namespace Prefix:	lmca_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Ratio applied to the exchange of shares of stock.

+ References

No definition available.

+ Details

Name:	lmca_StockholdersEquityExchangeConversionRatio
Namespace Prefix:	lmca_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of target voting power additional percentage.

+ References

No definition available.

+ Details

Name:	lmca_TargetVotingPowerAdditionalConditionalPercentage
Namespace Prefix:	lmca_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage of target voting power maximum.

+ References

No definition available.

+ Details

Name:	lmca_TargetVotingPowerPercentage
Namespace Prefix:	lmca_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The amount of upfront awards.

+ References

No definition available.

+ Details

Name:	lmca_UpfrontAwards
Namespace Prefix:	lmca_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Gross number of share options (or share units) granted during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(01)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	duration

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	us-gaap_TypeOfArrangementAxis=lmca_ExchangeAgreementWithChairmanMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	srt_TitleOfIndividualAxis=lmca_JohnC.MaloneChairmanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_StatementScenarioAxis=lmca_TargetVotingPowerPlusMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_StatementScenarioAxis=lmca_TargetVotingPowerLessMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementClassOfStockAxis=lmca_LibertyBravesGroupCommonClassCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementClassOfStockAxis=lmca_LibertyFormulaOneGroupCommonClassCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementClassOfStockAxis=us-gaap_CommonClassBMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	lmca_EconomicPerformanceGroupAxis=lmca_LibertySiriusXmGroupMember
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Data Type:	na
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- Details

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- Details

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Related Party Transactions with Officers and Directors (Details)		1 Months Ended		12 Months Ended
	Jan. 01, 2020	Dec. 31, 2020 USD ($) $ / shares shares	Dec. 31, 2019 USD ($) tranche $ / shares shares	Dec. 31, 2023 USD ($) shares	Dec. 31, 2022	Dec. 31, 2021	Jul. 28, 2021
Chief Executive Officer
Allocation percentage				54.00%	49.00%	41.00%
Relative market capitalization percentage				50.00%
Blended average of historical time allocation on a Liberty Media-wide and CEO basis weighted average				50.00%
Employment agreement term	5 years
Annual base salary				$ 3,000,000
One-time cash commitment bonus			$ 5,000,000
Annual target cash performance bonus				17,000,000
Upfront awards			$ 90,000,000
Number Of equal tranches \| tranche			2
Grant date fair value		$ 19,107,000	$ 19,800,000
Annual equity awards				$ 17,500,000
Exchange agreement with chairman \| John C. Malone
Target Voting Power Maximum							49.00%
Target Voting Power additional percentage							0.50%
Share exchanges \| shares				0
Target voting power plus percentage \| Exchange agreement with chairman \| John C. Malone
Target Voting Power Maximum							0.50%
Target voting power less percentage \| Exchange agreement with chairman \| John C. Malone
Target Voting Power additional percentage							0.50%
Liberty Sirius Xm Group Common Class C \| Chief Executive Officer
Options granted \| shares		665,140	927,334
Weighted average GDFV \| $ / shares		$ 42.13	$ 47.11
Liberty Braves Group Common Class C \| Chief Executive Officer
Options granted \| shares		352,224	313,342
Weighted average GDFV \| $ / shares		$ 26.36	$ 29.10
Liberty Formula One Group Common Class C \| Chief Executive Officer
Options granted \| shares		544,508	588,954
Weighted average GDFV \| $ / shares		$ 43.01	$ 43.85
Common Class B \| Liberty SiriusXM Group \| Exchange agreement with chairman \| John C. Malone
Stock exchange ratio				1
Common Class B \| Braves Group \| Exchange agreement with chairman \| John C. Malone
Stock exchange ratio				1
Common Class B \| Formula One Group \| Exchange agreement with chairman \| John C. Malone
Stock exchange ratio				1