Goodwill, Measurement Input

No definition available.

Name:	lgfa_GoodwillMeasurementInput
Namespace Prefix:	lgfa_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	instant

- Definition

License Agreement for Program Rights, Capitalized Cost, Noncurrent

+ References

No definition available.

+ Details

Name:	lgfa_LicenseAgreementforProgramRightsCapitalizedCostNoncurrent
Namespace Prefix:	lgfa_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Timing of payment (in days) in contract with customer from date of revenue recognition.

+ References

No definition available.

+ Details

Name:	lgfa_Revenueperformanceobligationtimingofpayment
Namespace Prefix:	lgfa_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 720
-SubTopic 35
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6420018&loc=d3e36677-107848

+ Details

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

- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(10)(1))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=120320667&loc=SL49117168-202975

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266

+ Details

Name:	us-gaap_Goodwill
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

+ Details

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

+ References

No definition available.

+ Details

Name:	us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_AdjustmentsForNewAccountingPronouncementsAxis=us-gaap_AccountingStandardsUpdate201902Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MeasurementInputTypeAxis=lgfa_MeasurementInputPerpetualNominalGrowthRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MeasurementInputTypeAxis=us-gaap_MeasurementInputDiscountRateMember
Namespace Prefix:
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- Details

Name:	srt_RangeAxis=srt_MaximumMember
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Description of Business, Basis of Presentation and Significant Accounting Policies (Other) (Details) $ in Millions	12 Months Ended
	Mar. 31, 2021 USD ($)	Mar. 31, 2020 USD ($)	Mar. 31, 2019 USD ($)	Apr. 01, 2020 USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Goodwill	$ 2,764.5	$ 2,833.5	$ 2,833.5
Indefinite-lived Intangible Assets (Excluding Goodwill)	250.0
Advertising expenses	$ 532.6	$ 782.4	$ 640.1
Timing of payment	60 days
Accounting for Costs of Films and License Agreements for Program Materials
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Non-current program rights				$ 310.5
Minimum \| Perpetual Nominal Growth Rate
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Goodwill measurement input		0.015
Minimum \| Discount Rate
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Goodwill measurement input		0.115
Maximum \| Perpetual Nominal Growth Rate
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Goodwill measurement input		0.040
Maximum \| Discount Rate
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Goodwill measurement input		0.15