Debt Instrument, Redemption Call Premium

No definition available.

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

- Definition

Repayments of Long-term Debt, Prepayment Premium

+ References

No definition available.

+ Details

Name:	lgfa_RepaymentsofLongtermDebtPrepaymentPremium
Namespace Prefix:	lgfa_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

Name:	us-gaap_DebtInstrumentCarryingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

+ Details

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
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.

+ References

No definition available.

+ Details

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

- Definition

Amount of the required periodic payments applied to principal.

+ References

+ Details

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

- Definition

Percentage of principal amount of debt redeemed.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentRedemptionPricePercentageOfPrincipalAmountRedeemed
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=49170532&loc=d3e12317-112629

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=49170532&loc=d3e12355-112629

+ Details

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

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

+ Details

Name:	us-gaap_LineOfCredit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The effective interest rate at the end of the reporting period.

+ References

+ Details

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

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3255-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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

- Details

Name:	us-gaap_DebtInstrumentAxis=lgfa_TermLoanBFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=lgfa_StarzMergerFinancingMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=lgfa_TermLoanDue2020Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_SecuredDebtMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=lgfa_A5.25SeniorNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_BaseRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_LondonInterbankOfferedRateLIBORMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_LoansPayableMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=lgfa_TermLoanAFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=lgfa_TermLoanDue2022Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_SeniorNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=lgfa_StarzSeniorNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BusinessAcquisitionAxis=lgfa_StarzMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Debt (Narrative - Debt Redemptions and Repayments) (Details) - USD ($) $ in Millions			1 Months Ended	12 Months Ended
	Dec. 08, 2016	Mar. 17, 2015	Mar. 31, 2017	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015	Feb. 28, 2017	Dec. 07, 2016
Debt Instrument [Line Items]
Debt Instrument, Redemption Call Premium		$ 4.5
Principal amount of debt outstanding			$ 3,107.5	$ 3,107.5	$ 786.0
Loss on extinguishment of debt				40.4	0.0	$ 11.7
Term Loan B Facility
Debt Instrument [Line Items]
Loss on extinguishment of debt				12.1		0.0
Starz Merger Financing
Debt Instrument [Line Items]
Loss on extinguishment of debt				3.2
Term Loan Due 2020
Debt Instrument [Line Items]
Loss on extinguishment of debt				$ 0.0		10.4
Senior Secured Second-Priority Notes \| 5.25% Senior Notes
Debt Instrument [Line Items]
Coupon rate			5.25%	5.25%
Prepayment premium	$ 15.0
Principal amount of debt outstanding	225.0		$ 0.0	$ 0.0	$ 225.0
Revolving Credit Facility
Debt Instrument [Line Items]
Outstanding obligations	241.0
Revolving credit facility, maximum borrowing capacity	1,000.0		$ 1,000.0	$ 1,000.0				$ 800.0
Effective interest rate			3.48%	3.48%	2.94%
Principal amount of debt outstanding			$ 0.0	$ 0.0	$ 161.0
Debt instrument, term				5 years
Revolving Credit Facility \| Base Rate
Debt Instrument [Line Items]
Basis spread on variable interest rate				1.50%
Revolving Credit Facility \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable interest rate				2.50%
Term Loan \| Term Loan B Facility
Debt Instrument [Line Items]
Effective interest rate			3.98%	3.98%
Principal amount of debt outstanding			$ 1,600.0	$ 1,600.0	0.0
Debt instrument, term				7 years
Principal amount of notes	2,000.0						$ 400.0
Term Loan \| Term Loan B Facility \| Base Rate
Debt Instrument [Line Items]
Basis spread on variable interest rate				2.00%
Term Loan \| Term Loan B Facility \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable interest rate				3.00%
Term Loan \| Term Loan A Facility
Debt Instrument [Line Items]
Effective interest rate			3.48%	3.48%
Principal amount of debt outstanding			$ 987.5	$ 987.5	0.0
Debt instrument, term				5 years
Principal amount of notes	$ 1,000.0
Term Loan A facility, required principal payment			12.5
Term Loan \| Term Loan A Facility \| Base Rate
Debt Instrument [Line Items]
Basis spread on variable interest rate				1.50%
Term Loan \| Term Loan A Facility \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable interest rate				2.50%
Term Loan \| Term Loan Due 2022
Debt Instrument [Line Items]
Coupon rate	5.00%
Prepayment premium	$ 8.0
Principal amount of debt outstanding	$ 400.0		$ 0.0	$ 0.0	$ 400.0
Debt instrument, term	7 years
Debt instrument redemption premium percentage, as a percentage of principal amount prepaid or redeemed				2.00%
Term Loan \| Term Loan Due 2020
Debt Instrument [Line Items]
Debt Instrument, Redemption Call Premium						$ 4.5
Debt instrument, term		7 years
Principal amount of notes		$ 225.0
Term Loan \| Term Loan Due 2020 \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable interest rate		4.00%
Senior Notes \| Starz Senior Notes
Debt Instrument [Line Items]
Prepayment premium	$ 8.4
Principal amount of debt outstanding	675.0
Starz \| Starz Merger Financing
Debt Instrument [Line Items]
Proceeds from revolving credit facility used to finance a portion of Starz merger consideration	50.0
Starz \| Revolving Credit Facility
Debt Instrument [Line Items]
Outstanding obligations	$ 255.0
Revolving credit facility, maximum borrowing capacity								$ 1,000.0
Minimum \| Term Loan \| Term Loan B Facility \| LIBOR
Debt Instrument [Line Items]
Coupon rate			0.75%	0.75%
Minimum \| Term Loan \| Term Loan Due 2020 \| LIBOR
Debt Instrument [Line Items]
Coupon rate		1.00%