Face amount or stated value per share of common stock.

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-Topic 210
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-Paragraph 1
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- Definition

Balance held at close of period in number of shares.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
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-Section 50
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The number of countries in which the entity operates as of balance sheet date.

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

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- Definition

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

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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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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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Number of songwriters and composers.

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Sale Of Stock, Percentage Of Economic Interest

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Description of Business - Additional Information (Details) musical_composition in Millions			12 Months Ended
	Jul. 07, 2020 shares	Jun. 05, 2020 $ / shares shares	Sep. 30, 2020 country musical_composition $ / shares songwriter shares	Sep. 30, 2019 $ / shares
Subsidiary, Sale of Stock [Line Items]
Number of countries in which operations are conducted \| country			70
Minimum number of musical compositions on which Company owns or controls rights \| musical_composition			1,000,000
Number of songwriters and composers \| songwriter			80,000
Access Industries
Subsidiary, Sale of Stock [Line Items]
Sale of stock, percentage of ownership after transaction		99.00%
Sale of stock, percentage of economic interest		83.00%
IPO
Subsidiary, Sale of Stock [Line Items]
Sale of stock (in usd per share)			$ 25
Common Class A
Subsidiary, Sale of Stock [Line Items]
Common stock, par value (in usd per share)			0.001	$ 0.001
Common Class A \| IPO
Subsidiary, Sale of Stock [Line Items]
Sale of stock (in shares) \| shares		77,000,000
Common stock, par value (in usd per share)		$ 0.001
Sale of stock (in usd per share)		$ 25
Common Class A \| Over-Allotment Option
Subsidiary, Sale of Stock [Line Items]
Sale of stock (in shares) \| shares	11,550,000
Common Class B
Subsidiary, Sale of Stock [Line Items]
Common stock, par value (in usd per share)			0.001	$ 0.001
Common Class B \| Access Industries
Subsidiary, Sale of Stock [Line Items]
Common stock, par value (in usd per share)			$ 0.001
Investment owned, balance, shares (in shares) \| shares			421,450,000