Segment Information - Purchase Accounting and Related Adjustments (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2025	Mar. 31, 2024	Mar. 31, 2023
General and administration
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Purchase accounting and related adjustments	$ 8.7	$ 12.0	$ 55.2
General and administration | Lions Gate Entertainment Corp.
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Purchase accounting and related adjustments	8.7	11.6
Corporate and Reconciling Items
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Purchase accounting and related adjustments	12.9	17.1	61.6
Corporate and Reconciling Items | Lions Gate Entertainment Corp.
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Purchase accounting and related adjustments	163.0	153.7	195.5
Corporate and Reconciling Items | Direct operating | Lions Gate Entertainment Corp.
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Purchase accounting and related adjustments	0.0	0.0	0.7
Corporate and Reconciling Items | General and administration
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Purchase accounting and related adjustments	8.7	12.0	55.2
Amortization of recoupable portion of the purchase price	0.0	1.3	7.7
Noncontrolling interest discount amortization	0.0	0.0	13.2
Noncontrolling equity interest in distributable earnings	8.7	10.7	34.3
Corporate and Reconciling Items | General and administration | Lions Gate Entertainment Corp.
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Purchase accounting and related adjustments	8.7	11.6	54.7
Amortization of recoupable portion of the purchase price	0.0	1.3	7.7
Noncontrolling interest discount amortization	0.0	0.0	13.2
Noncontrolling equity interest in distributable earnings	8.7	10.3	33.8
Corporate and Reconciling Items | Depreciation and Amortization Expense
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Purchase accounting and related adjustments	4.2	5.1	5.7
Corporate and Reconciling Items | Depreciation and Amortization Expense | Lions Gate Entertainment Corp.
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Purchase accounting and related adjustments	$ 154.3	$ 142.1	$ 140.1