Significant Accounting Policies (Investment in Films and Television Programs) (Details) - USD ($) $ in Millions	12 Months Ended
Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Significant Accounting Policies [Abstract]
Capitalized interest for films and television programs produced	$ 8.7	$ 19.9	$ 15.6
Ultimate revenue, estimates used, maximum term, motion picture	10 years
Ultimate revenue, estimates used, maximum term, television series	10 years
Ultimate revenue, estimates used, term, television series still in production	5 years
Ultimate revenue, estimates used, maximum term, acquired libraries	20 years
Projects in development, potential trigger for write-off of development costs, time period from date of initial investment	3 years
Film and television program impairment charges	$ 22.7	$ 25.0

Impairment charges on film and television programs.

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- Definition

Projects in Development, Potential Trigger for Write-off of Development Costs, Time Period from Date of Initial Investment

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- Definition

Significant Accounting Policies [Abstract]

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- Definition

Maximum period over which ultimate revenues are estimated following the date of acquisition for titles included in acquired libraries.

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- Definition

Maximum period over which ultimate revenues are estimated following the date of initial release for a motion picture.

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- Definition

Maximum period over which ultimate revenues are estimated following the date of delivery of the first episode, or, if still in production, five years from date of delivery of most recent episode, if later.

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- Definition

For an episodic television series still in production, period over which ultimate revenues are estimated following the date of delivery of the most recent episode, if later than ten years following the date of delivery of the first episode.

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- Definition

Amount of interest capitalized during the period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Allowance for Funds Used during Construction
-URI http://asc.fasb.org/extlink&oid=6504829

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391

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