Percentage of the entity's common stock outstanding owned by a related party.

No definition available.

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Balance Type:	na
Period Type:	instant

- Definition

Related party, percentage owned of entity.

+ References

No definition available.

+ Details

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Namespace Prefix:	lgfa_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3213-108585

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Amount of transactions with related party during the financial reporting period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39622-107864

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39603-107864

+ Details

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

- Definition

Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

+ Details

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

- 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.

+ References

No definition available.

+ Details

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Period Type:	duration

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=srt_BoardOfDirectorsChairmanMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=srt_DirectorMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=us-gaap_EquityMethodInvesteeMember
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- Details

Name:	srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=lgfa_AtomTicketsMember
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Data Type:	na
Balance Type:
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- Details

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- Details

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- Details

Name:	us-gaap_StatementClassOfStockAxis=us-gaap_CommonClassBMember
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Data Type:	na
Balance Type:
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- Details

Name:	srt_RangeAxis=srt_MaximumMember
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Related Party Transactions (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018	May 18, 2020
Chairman of the Board of Directors
Related Party Transaction [Line Items]
Related party expenses incurred		$ 0.8	$ 1.2
Director
Related Party Transaction [Line Items]
Related party expenses incurred	$ 1.6	2.4	4.4
Related party, ownership percentage of entity	100.00%
Related party transaction, amounts paid			0.1
Equity Method Investees
Related Party Transaction [Line Items]
Related party expenses incurred	$ 13.8	32.2	22.0
Atom Tickets \| Equity Method Investees
Related Party Transaction [Line Items]
Investment in equity method investees			$ 10.0
Class A Voting Common Shares \| Subsequent Event \| Chairman of the Board of Directors
Related Party Transaction [Line Items]
Percentage of common stock outstanding held by MHR Fund Management				23.00%
Class B Non-Voting Common Shares \| Subsequent Event \| Chairman of the Board of Directors
Related Party Transaction [Line Items]
Percentage of common stock outstanding held by MHR Fund Management				11.00%
Maximum \| Chairman of the Board of Directors
Related Party Transaction [Line Items]
Related party expenses incurred	0.1
Maximum \| Director
Related Party Transaction [Line Items]
Related party transaction, amounts paid	$ 0.0	$ 0.1