Derivative, Second Term of Contract.

No definition available.

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- Definition

The portion of redeemable noncontrolling interest, expressed as a percentage of the company acquired, that is redeemable at the completion of the first term.

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No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

+ Details

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Period Type:	duration

- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Period Type:	duration

- Definition

Value of new stock classified as temporary equity issued during the period.

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No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	dei_LegalEntityAxis=lgfa_PilgrimMediaGroupMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Noncontrolling Interests (Narrative) (Details) - USD ($) $ in Millions		12 Months Ended
	Nov. 12, 2015	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Redeemable Noncontrolling Interest [Line Items]
Initial fair value of redeemable noncontrolling interests		$ 0.0	$ 0.0	$ 90.1
Pilgrim Media Group
Redeemable Noncontrolling Interest [Line Items]
Initial fair value of redeemable noncontrolling interests	$ 90.1
Redeemable noncontrolling interest, ownership percentage held by noncontrolling owner	37.50%
Portion of noncontrolling interest redeemable after first term, five years after November 12, 2015		17.50%
First Put/ Call Option, Term		5 years
Second Put/ Call Option, Term		7 years