Revenue Recognition - Summary of Revenues Disaggregated Based on Timing of Revenue Recognition (Detail) - USD ($) $ in Millions		3 Months Ended				9 Months Ended
		Sep. 30, 2024		Sep. 30, 2023		Sep. 30, 2024		Sep. 30, 2023
Disaggregation of Revenue [Line Items]
Total revenue		$ 921.8		$ 874.8		$ 2,235.2		$ 2,427.8
Goods and Services Transferred at a Point in Time
Disaggregation of Revenue [Line Items]
Total revenue		874.1		831.2		2,113.2		2,305.7
Goods and Services Transferred Over Time
Disaggregation of Revenue [Line Items]
Total revenue		47.7	[1]	43.6	[2]	122.0	[1]	122.1	[2]
U.S. Operating Segment
Disaggregation of Revenue [Line Items]
Total revenue	[3]	741.4		682.5		1,770.4		1,896.5
U.S. Operating Segment | Goods and Services Transferred at a Point in Time
Disaggregation of Revenue [Line Items]
Total revenue	[4]	714.6		657.4		1,696.1		1,819.9
U.S. Operating Segment | Goods and Services Transferred Over Time
Disaggregation of Revenue [Line Items]
Total revenue	[4]	26.8	[1]	25.1	[2]	74.3	[1]	76.6	[2]
International Operating Segment
Disaggregation of Revenue [Line Items]
Total revenue		180.4		192.3		464.8		531.3
International Operating Segment | Goods and Services Transferred at a Point in Time
Disaggregation of Revenue [Line Items]
Total revenue		159.5		173.8		417.1		485.8
International Operating Segment | Goods and Services Transferred Over Time
Disaggregation of Revenue [Line Items]
Total revenue		$ 20.9	[1]	$ 18.5	[2]	$ 47.7	[1]	$ 45.5	[2]

[1] Amount includes amortization of NCM screen advertising advances. See Screen Advertising Advances and Other Deferred Revenue below.

[2] Amount includes amortization of NCM screen advertising advances. See Screen Advertising Advances and Other Deferred Revenue below.

[3] U.S. segment revenue excludes intercompany transactions with the international operating segment. See Note 16 for the amount of intercompany eliminations for the periods presented.

[4] U.S. segment revenue excludes intercompany transactions with the international operating segment. See Note 16 for the amount of intercompany eliminations for the periods presented.