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Amount of revenue recognized from performance obligation satisfied or partially satisfied in previous reporting periods. Includes, but is not limited to, change in transaction price.

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Amount of liability for consideration received or receivable from customer which is not included in transaction price, when consideration is expected to be refunded to customer.

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Revenue Recognition - Additional Information (Detail) $ in Millions	3 Months Ended
	Dec. 31, 2021 USD ($) source	Dec. 31, 2020 USD ($)	Sep. 30, 2021 USD ($)
Disaggregation of Revenue [Line Items]
Refund liabilities	$ 33		$ 23
Uncollectible accounts, reserves	20		$ 20
Deferred revenue increased related to cash received from customers	104
Revenue recognized related to deferred revenue	135
Revenue recognized from performance obligations satisfied in previous periods	$ 37	$ 20
Recorded Music
Disaggregation of Revenue [Line Items]
Number of revenue sources \| source	4
Music Publishing
Disaggregation of Revenue [Line Items]
Number of revenue sources \| source	5