Additional Financial Information (Non-Cash Investing and Financing Activities) (Details) - USD ($) $ in Millions	12 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2019
Non-cash investing activities
Consideration receivable for Pantaya sale	$ 123.6	$ 0.0	$ 0.0
Decrease in finance lease right-of-use asset due to a reassessment event	(42.0)	0.0
Issuance of common shares related to business acquisitions	0.0	0.0	$ 83.7
Non-cash financing activities
Decrease in finance lease liability due to a reassessment event	$ (48.6)	$ 0.0

Amount of noncash consideration received for selling an asset or business through a noncash (or part noncash) transaction.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
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