Investments in Affiliates - Summary of Activity for Each of Company's Investments in affiliates (Detail) - Other Affiliates [Member] $ in Millions	9 Months Ended
	Sep. 30, 2024 USD ($)
Schedule Of Equity Method Investments [Line Items]
Investments, beginning balance	$ 23.6
Cash distributions received	(5.1)
Equity income	11.3
Investments, ending balance	29.8
AC JV, LLC
Schedule Of Equity Method Investments [Line Items]
Investments, beginning balance	3.4
Cash distributions received	(5.1)
Equity income	9.6
Investments, ending balance	7.9
Digital Cinema Distribution Coalition
Schedule Of Equity Method Investments [Line Items]
Investments, beginning balance	2.1
Cash distributions received	0.0
Equity income	0.4
Investments, ending balance	2.5
FE Concepts, LLC
Schedule Of Equity Method Investments [Line Items]
Investments, beginning balance	18.1
Cash distributions received	0.0
Equity income	1.3
Investments, ending balance	$ 19.4