Restructuring and Other (Restructuring and Other) (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Restructuring Cost and Reserve [Line Items]
Restructuring and other		$ 15.0	$ 3.5	$ 25.6	$ 14.4
Severance
Restructuring Cost and Reserve [Line Items]
Restructuring and other	[1]	2.9	0.0	3.7	1.0
Severance | Accounts Payable and Accrued Liabilities
Restructuring Cost and Reserve [Line Items]
Remaining severance liability, expected to be paid in next 12 months		7.0		7.0
Transaction and related costs
Restructuring Cost and Reserve [Line Items]
Restructuring and other	[2]	$ 12.1	$ 3.5	$ 21.9	$ 13.4

[1] Severance costs in the three and six months ended September 30, 2018 and the six months ended September 30, 2017 were primarily related to restructuring activities in connection with recent acquisitions, and other cost-saving initiatives. As of September 30, 2018, the remaining severance liability was approximately $7.0 million, which is expected to be paid in the next 12 months.

[2] Transaction and related costs in the three and six months ended September 30, 2018 and 2017 reflect transaction, integration and legal costs associated with certain strategic transactions and legal matters. In the three and six months ended September 30, 2018, these costs were primarily related to the legal fees associated with the Starz class action lawsuits and other matters, and to a lesser extent, costs related to the acquisition of 3 Arts Entertainment and other strategic transactions. In the three and six months ended September 30, 2017, these costs were primarily related to the sale of EPIX (see Note 4), the legal fees associated with the Starz class action lawsuits and other matters, and the integration of Starz.