Segment Information - Schedule of Adjusted Depreciation and Amortization (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2023	Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2022
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Depreciation and amortization					$ 15.6	$ 17.9	$ 18.1
Less: Amount included in purchase accounting and related adjustments					(5.1)	(5.7)	(5.7)
Adjusted depreciation and amortization	$ 3.4	$ 1.8	$ 10.1	$ 7.1	10.5	12.2	12.4
Depreciation and amortization	4.4	3.0	13.2	11.1	15.6	17.9	18.1
Corporate and Reconciling Items
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Adjusted depreciation and amortization	3.4	1.8	10.1	7.1
Purchase Accounting and Related Adjustments \| Corporate and Reconciling Items
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Depreciation and amortization	$ (1.0)	$ (1.2)	(3.1)	(4.0)
Starz Business of Lions Gate Entertainment Corp
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Depreciation and amortization			122.2	118.7	161.8	155.7	152.6
Less: Amount included in purchase accounting and related adjustments			(107.2)	(101.5)	(137.0)	(134.4)	(129.3)
Adjusted depreciation and amortization			15.0	17.2	24.8	21.3	23.3
Depreciation and amortization			$ 122.2	$ 118.7	$ 161.8	$ 155.7	$ 152.6

Adjusted depreciation and amortization.

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- Definition

Business combination purchase accounting adjustment of depreciation and amortization.

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- Definition

The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production.

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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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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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