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Restructuring and Impairments - Additional Information (Details) - USD ($) $ in Millions		3 Months Ended			9 Months Ended
	Jul. 01, 2025	Dec. 31, 2026	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Recorded Music
Restructuring Cost and Reserve [Line Items]
Other impairments charges			$ 3	$ 70	$ 14	$ 70
2025 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Pre-tax basis	$ 200
After-tax basis	150
Cash expenditures	200
Cumulative restructuring and impairment charges			152		152
Restructuring charges				$ 0		$ 0
2025 Restructuring Plan \| Forecast
Restructuring Cost and Reserve [Line Items]
Payment for restructuring		$ 170
2025 Restructuring Plan \| Operating Segments \| Recorded Music
Restructuring Cost and Reserve [Line Items]
Cumulative restructuring and impairment charges			100		100
2025 Restructuring Plan \| Operating Segments \| Music Publishing
Restructuring Cost and Reserve [Line Items]
Cumulative restructuring and impairment charges			5		5
2025 Restructuring Plan \| Corporate expenses and eliminations
Restructuring Cost and Reserve [Line Items]
Cumulative restructuring and impairment charges			47		47
2025 Restructuring Plan \| Severance Costs
Restructuring Cost and Reserve [Line Items]
Pre-tax basis	170
Payment for restructuring					80
Severance and other terminated costs					124
Restructuring charges					$ 34
Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration]					Restructuring & Impairment
2025 Restructuring Plan \| Other Non-cash Charges
Restructuring Cost and Reserve [Line Items]
Pre-tax basis	$ 30
2025 Restructuring Plan \| Severance And Other Termination Costs
Restructuring Cost and Reserve [Line Items]
Severance and other terminated costs			4		$ 34
2025 Restructuring Plan \| Severance And Other Termination Costs \| Operating Segments \| Recorded Music
Restructuring Cost and Reserve [Line Items]
Severance and other terminated costs			3		21
2025 Restructuring Plan \| Severance And Other Termination Costs \| Corporate expenses and eliminations
Restructuring Cost and Reserve [Line Items]
Severance and other terminated costs			1		13
2025 Restructuring Plan \| Property Wind Down
Restructuring Cost and Reserve [Line Items]
Restructuring charges					28
2024 Strategic Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Payment for restructuring					22
Cumulative restructuring and impairment charges			215		215
Restructuring charges					(1)
2024 Strategic Restructuring Plan \| Operating Segments \| Recorded Music
Restructuring Cost and Reserve [Line Items]
Cumulative restructuring and impairment charges			206		206
2024 Strategic Restructuring Plan \| Corporate expenses and eliminations
Restructuring Cost and Reserve [Line Items]
Cumulative restructuring and impairment charges			$ 9		9
2024 Strategic Restructuring Plan \| Severance Costs
Restructuring Cost and Reserve [Line Items]
Payment for restructuring					16
Restructuring charges					(1)
2024 Strategic Restructuring Plan \| Other Non-cash Charges
Restructuring Cost and Reserve [Line Items]
Restructuring charges					7
2024 Strategic Restructuring Plan \| Severance And Other Termination Costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges					$ 133
Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration]					Restructuring & Impairment
2024 Strategic Restructuring Plan \| Property Wind Down
Restructuring Cost and Reserve [Line Items]
Restructuring charges					$ 82