Business Combination, Consideration Transferred, Liabilities Accrued

No definition available.

Name:	lgfa_BusinessCombinationConsiderationTransferredLiabilitiesAccrued
Namespace Prefix:	lgfa_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amounts received in settlement of a claim for reimbursement from an insurance company when the Company has suffered a loss covered under an insurance policy.

+ References

No definition available.

+ Details

Name:	lgfa_InsuranceReimbursementAmount
Namespace Prefix:	lgfa_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amortization of non-cash fair value adjustments to the assets and liabilities acquired in the acquisition of businesses.

+ References

No definition available.

+ Details

Name:	lgfa_PurchaseAccountingandRelatedAdjustments
Namespace Prefix:	lgfa_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of gain (loss) recognized in settlement of litigation and insurance claims. Excludes claims within an insurance entity's normal claims settlement process.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118942415&loc=d3e14326-108349

+ Details

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

- Definition

Amount awarded to other party in judgment or settlement of litigation.

+ References

No definition available.

+ Details

Name:	us-gaap_LitigationSettlementAmountAwardedToOtherParty
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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

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

- Details

Name:	srt_ConsolidationItemsAxis=lgfa_CorporateAndReconcilingItemsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_IncomeStatementLocationAxis=us-gaap_OperatingExpenseMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_IncomeStatementLocationAxis=us-gaap_GeneralAndAdministrativeExpenseMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_IncomeStatementLocationAxis=lgfa_DepreciationandAmortizationExpenseMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_LitigationCaseAxis=lgfa_FiduciaryLitigationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_LitigationCaseAxis=lgfa_AppraisalLitigationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Segment Information (Purchase Accounting and Related Adjustments and Shareholder Litigation Settlements) (Details) - USD ($) $ in Millions		3 Months Ended	12 Months Ended
	Oct. 09, 2018	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018	Dec. 08, 2016
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Shareholder litigation settlements			$ 0.0	$ 114.1	$ 0.0
Corporate and reconciling items
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Purchase accounting and related adjustments			216.6	184.1	170.3
Direct operating \| Corporate and reconciling items
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Purchase accounting and related adjustments			8.1	18.0	44.5
General and administrative expense
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Purchase accounting and related adjustments			52.6	43.8
General and administrative expense \| Corporate and reconciling items
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Purchase accounting and related adjustments			52.6	43.8	6.1
Depreciation and amortization expense \| Corporate and reconciling items
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Purchase accounting and related adjustments			$ 155.9	122.3	$ 119.7
Fiduciary Litigation
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Shareholder litigation settlements				54.8
Settlement payment amount	$ 92.5			92.5
Insurance reimbursement, amount		$ 37.8		37.8
Appraisal Litigation
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Shareholder litigation settlements				59.3
Settlement payment amount				$ 964.0
Value of original merger consideration, dissenting shareholders liability accrued at time of acquisition						$ 797.3