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

No definition available.

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- Definition

Amount of cash payments reattributed to Liberty Live Holdings, Inc.

+ References

No definition available.

+ Details

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

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22)(a)(1))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

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Balance Type:	na
Period Type:	instant

- Definition

Amount of transactions with related party during the financial reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483326/850-10-50-1

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Balance Type:	debit
Period Type:	duration

- Details

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- Details

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- Details

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Basis of Presentation (Details) - USD ($) $ in Millions		3 Months Ended
Basis of Presentation (Details) - USD ($) $ in Millions	Dec. 15, 2025	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025	Dec. 14, 2025
Formula One Group
Basis of Presentation
Payment to Liberty Live Holdings, Inc.	$ 172
Affiliated Entity \| QVC Group, Liberty Broadband, GCI Liberty, Atlanta Braves Holdings and TripCo
Basis of Presentation
Allocated expenses		$ 5	$ 5
2.25% Convertible Senior Notes due 2027
Basis of Presentation
Debt instrument interest rate (as a percent)		2.25%		2.25%
2.25% Convertible Senior Notes due 2027 \| Formula One Group
Basis of Presentation
Debt instrument interest rate (as a percent)					2.25%