Face amount or stated value per share of common stock.

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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Balance held at close of period in number of shares.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 210
-Section 50
-Paragraph 6
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The number of countries in which the entity operates as of balance sheet date.

+ References

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- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

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- Definition

Percentage of subsidiary's or equity investee's stock owned by parent company after stock transaction.

+ References

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- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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- Definition

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.

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- Definition

Minimum number of musical compositions on which rights are owned or controlled.

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- Definition

Number of songwriters and composers.

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- Definition

Sale Of Stock, Percentage Of Economic Interest

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Description of Business - Additional Information (Detail)			6 Months Ended
	Jul. 07, 2020 shares	Jun. 05, 2020 $ / shares shares	Mar. 31, 2021 country musical_composition $ / shares songwriter	Sep. 30, 2020 $ / shares
Subsidiary, Sale of Stock [Line Items]
Number of countries in which recorded music activity conducted (more than) \| country			70
Minimum number of musical compositions on which Company owns or controls rights (more than) \| musical_composition			1,000,000,000,000
Number of songwriters and composers (over) \| songwriter			80,000
Access Industries
Subsidiary, Sale of Stock [Line Items]
Percentage of voting power		99.00%
Percentage of economic interest		83.00%
Class A Common Stock
Subsidiary, Sale of Stock [Line Items]
Par value (in dollars per share)			$ 0.001	$ 0.001
Class B Common Stock
Subsidiary, Sale of Stock [Line Items]
Par value (in dollars per share)			$ 0.001	$ 0.001
Class B Common Stock \| Access Industries
Subsidiary, Sale of Stock [Line Items]
Par value (in dollars per share)		$ 0.001
Investment owned (in shares) \| shares		421,450,000
IPO \| Class A Common Stock
Subsidiary, Sale of Stock [Line Items]
Number of shares issued in transaction (in shares) \| shares		77,000,000
Par value (in dollars per share)		$ 0.001
Price per share (in dollars per share)		$ 25
Over-Allotment Option \| Class A Common Stock
Subsidiary, Sale of Stock [Line Items]
Number of shares issued in transaction (in shares) \| shares	11,550,000