Subsequent Events (Detail) - Subsequent Event $ / shares in Units, $ in Millions		1 Months Ended
Feb. 21, 2024 right $ / shares	Feb. 29, 2024 USD ($)
Subsequent Event [Line Items]
Percentage of rights plan, beneficial ownership	15.00%
Class A Common Stock
Subsequent Event [Line Items]
Number of rights, dividends declared \| right	1
Share price (in USD per share) \| $ / shares	$ 25.00
Conversion ratio	0.0001
Class B Common Stock
Subsequent Event [Line Items]
Number of rights, dividends declared \| right	1
Share price (in USD per share) \| $ / shares	$ 25.00
Conversion ratio	0.0001
New Mountain Capital, LLC \| Broadcast Music, Inc. \| Discontinued Operations, Disposed of by Sale
Subsequent Event [Line Items]
Cash proceeds received \| $		$ 14.8

Number Of Rights, Dividends Declared

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- Definition

Rights Plan, Beneficial Ownership Percentage Of Common Stock

+ References

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- Definition

The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-12

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

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- Definition

Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section S99
-Paragraph 4
-Subparagraph (SAB TOPIC 4.C)
-SubTopic 10
-Topic 505
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480008/505-10-S99-4

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 830
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481674/830-30-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483399/855-10-50-2

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