Capital lease net annual rental payment.

No definition available.

Name:	bgi_CapitalLeaseNetAnnualRentalPayment
Namespace Prefix:	bgi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Capital leases expiration period.

+ References

No definition available.

+ Details

Name:	bgi_CapitalLeasesExpirationPeriod
Namespace Prefix:	bgi_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Line of credit covenant long term debt to adjusted net assets.

+ References

No definition available.

+ Details

Name:	bgi_LineOfCreditCovenantLongTermDebtToAdjustedNetAssets
Namespace Prefix:	bgi_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

- Definition

Line of credit covenant working capital ratio minimum.

+ References

No definition available.

+ Details

Name:	bgi_LineOfCreditCovenantWorkingCapitalRatioMinimum
Namespace Prefix:	bgi_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

- Definition

Reduction of monthly capital requirements.

+ References

No definition available.

+ Details

Name:	bgi_ReductionOfMonthlyCapitalRequirements
Namespace Prefix:	bgi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6455398&loc=d3e45280-112737

Reference 2: 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 3: 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(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

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

- Definition

Amount before accumulated depreciation of leased physical assets used in the normal conduct of business to produce goods and services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6455314&loc=d3e45014-112735

+ Details

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

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

Name:	us-gaap_LettersOfCreditOutstandingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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_LineOfCreditFacilityLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of the gain recorded in connection with the transaction involving the sale of property to another party and the lease of the property back to the seller to be recognized in future periods.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 40
-Section 25
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6456126&loc=d3e49567-112750

+ Details

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

- Details

Name:	us-gaap_SaleLeasebackTransactionDescriptionAxis=bgi_HeadOfficeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BalanceSheetLocationAxis=us-gaap_OtherNoncurrentLiabilitiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ShortTermDebtTypeAxis=bgi_InvestissementQuebecMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix:
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Period Type:

Long-term debt - Additional Information (Detail) CAD in Millions, $ in Millions	1 Months Ended		12 Months Ended
	Nov. 30, 2015 USD ($)	Nov. 30, 2015 CAD	Mar. 25, 2017 USD ($)	Dec. 11, 2016 USD ($)	Dec. 11, 2016 CAD	Mar. 26, 2016 USD ($)
Line of Credit Facility [Line Items]
Outstanding letters of credit			$ 0.9			$ 1.0
Montreal Head Office and Store [Member]
Line of Credit Facility [Line Items]
Capital lease asset				$ 6.5	CAD 8.7
Capital lease obligation				8.7	11.6
Lease period			20 years
Annual rent rate				1.6	2.2
Montreal Head Office and Store [Member] \| Other Long-term Liabilities [Member]
Line of Credit Facility [Line Items]
Non-cash gain				$ 2.2	CAD 2.9
Investissement Quebec [Member]
Line of Credit Facility [Line Items]
Reduction of monthly capital requirements	$ 1.5	CAD 2.0
Minimum capital ratio required			1.15
Investissement Quebec [Member] \| Minimum [Member]
Line of Credit Facility [Line Items]
Adjusted long-term debt to adjusted net assets ratio			2.5