Additional Financial Information - Summary of Cash and Cash Equivalents and Cash in Assets of Discontinued Operations (Details) - USD ($) $ in Millions	Dec. 31, 2024	Mar. 31, 2024	Mar. 31, 2023
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	$ 186.2	$ 277.0	$ 210.9
Starz Business of Lions Gate Entertainment Corp
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	14.2	23.0	52.0
Cash in assets of discontinued operations - current	0.0	14.0	9.6
Total cash, cash equivalents and cash in assets of discontinued operations	$ 14.2	$ 37.0	$ 61.6

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
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-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
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-Publisher FASB
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