Government Assistance (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Mar. 31, 2014
Government Assistance [Abstract]
Tax credits earned for film and television production activity	$ 103.5	$ 15.0	$ 193.0	$ 62.0
Tax credits receivable for film and television production	$ 272.9		$ 272.9		$ 115.3

Tax credits earned for film and television production activity that are recorded as a reduction of the cost of the related film and television program.

No definition available.

Name:	lgf_TaxCreditsEarnedForFilmAndTelevisionProductionActivity
Namespace Prefix:	lgf_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration