Debt instrument covenant fixed charge coverage ratio.

No definition available.

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

- Definition

Line of credit facility additional borrowing capacity.

+ References

No definition available.

+ Details

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

- Definition

Line of credit facility excess availability trigger percentage.

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line of credit facility excess availability trigger percentage of line cap.

+ References

No definition available.

+ Details

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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

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-Paragraph 1
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Balance Type:	credit
Period Type:	instant

- Definition

Description of minimum financial levels (for example, tangible net worth and working capital) and achievement of certain financial ratios (for example, working capital ratio and debt service coverage ratio), and adherence to certain clauses which generally require or restrict certain actions (for example, entering into a debt arrangement with equal or greater seniority, and selling or discontinuing a certain business segment or material subsidiary) to be in compliance with the covenant clauses of the debt agreement. May also include a discussion of the adverse consequences that would result if the entity violates or fails to satisfy the covenants.

+ References

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
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Balance Type:	na
Period Type:	duration

- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Balance Type:	debit
Period Type:	instant

- 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.

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-Paragraph 1
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+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-SubTopic 10
-Name Accounting Standards Codification
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Balance Type:	credit
Period Type:	instant

- Definition

Fair value of the amount outstanding under the credit facility.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 825
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-Name Accounting Standards Codification
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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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
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Balance Type:	na
Period Type:	duration

- 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

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Balance Type:	credit
Period Type:	instant

- Definition

The carrying value as of the balance sheet date of the current portion 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

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-SubTopic 10
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Balance Type:	credit
Period Type:	instant

- Definition

Mortgage loan related to property sales in noncash investing and financing activities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
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-SubTopic 10
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Balance Type:	credit
Period Type:	duration

- Definition

Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 942
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-Name Accounting Standards Codification
-Section S99
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-Subparagraph (SX 210.12-04(a))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-3

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Balance Type:	credit
Period Type:	instant

- Definition

The portion of the carrying amount of short-term borrowings outstanding as of the balance sheet date, which accrues interest at a rate subject to change from time to time.

+ References

No definition available.

+ Details

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- Details

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- Details

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Bank Indebtedness - Additional Information (Detail) - CAD ($) $ in Thousands			12 Months Ended
	Dec. 24, 2021	Oct. 23, 2017	Mar. 28, 2026	Jul. 08, 2025	Mar. 29, 2025	Sep. 06, 2024	Jul. 15, 2024	Jun. 26, 2024	Jun. 29, 2018
Line of Credit Facility [Line Items]
Bank indebtedness			$ 71,671		$ 73,630
New credit facility maturity date	Dec. 31, 2026
Minimum excess availability percentage of borrowings			40.00%
Minimum excess availability percentage of line cap			25.00%
Mortgage on movable property (general) under the Civil Code (Quebec)			$ 200,000
Credit Facility [Member]
Line of Credit Facility [Line Items]
Senior secured credit facility		$ 85,000				$ 90,000
New credit facility maturity date		Oct. 31, 2022
Total commitments		$ 5,000
Line of Credit Facility, Current Borrowing Capacity						$ 5,000
Term Loan [Member]
Line of Credit Facility [Line Items]
Long-term senior secured term loan									$ 12,500
Amended Credit Facility [Member]
Line of Credit Facility [Line Items]
Bank indebtedness			71,700		73,600
Long-term debt, gross			72,000		73,800
Senior secured revolving credit facility, excess availability			17,600		15,500
New credit facility maturity date	Dec. 31, 2026
Net of deferred financing costs			$ 300		$ 200
Amended Term Loan [Member]
Line of Credit Facility [Line Items]
Interest rate of CORRA plus spread									7.00%
Fair value of amount outstanding				$ 116,000
Amended Term Loan [Member] \| Canadian Overnight Repo Rate Average [Member]
Line of Credit Facility [Line Items]
Interest rate of CORRA plus spread								0.32%
Amended Term Loan [Member] \| Canadian Dollar Offered Rate [Member]
Line of Credit Facility [Line Items]
Interest rate of CORRA plus spread								7.00%
Amended Credit Facility And Amended Term Loan [Member]
Line of Credit Facility [Line Items]
Debt instrument, covenant description			In the event that minimum excess availability as defined in the Amended Credit Facility and Amended Term Loan is not maintained in accordance with the Company’s Amended Credit Facility and its Amended Term Loan, this would be considered an event of default thereunder that provides the lenders the right to require the outstanding balances borrowed under the Company’s Amended Credit Facility and its Amended Term Loan become due immediately, which would result in cross defaults on the Company’s other borrowings. The Company expects to have minimum excess availability as defined in the Wells Credit Facility and GB Term Loan for at least the next twelve months from the date of issuance of these financial statements.
Line of Credit Facility, Current Borrowing Capacity							$ 2,750
Incremental Loan [Member]
Line of Credit Facility [Line Items]
Senior secured credit facility				13,500
Senior Secured Lenders [Member]
Line of Credit Facility [Line Items]
Senior secured credit facility				$ 90,000
Maximum [Member]
Line of Credit Facility [Line Items]
Fixed charge coverage ratio			1.1
Maximum [Member] \| Amended Credit Facility [Member]
Line of Credit Facility [Line Items]
Interest rate of CORRA plus spread		2.00%						2.00%
Maximum [Member] \| Amended Credit Facility [Member] \| Canadian Overnight Repo Rate Average [Member]
Line of Credit Facility [Line Items]
Interest rate of CORRA plus spread								0.32%
Maximum [Member] \| Amended Term Loan [Member]
Line of Credit Facility [Line Items]
Interest rate of CORRA plus spread									7.75%
Maximum [Member] \| Amended Term Loan [Member] \| Canadian Overnight Repo Rate Average [Member]
Line of Credit Facility [Line Items]
Interest rate of CORRA plus spread								7.75%
Maximum [Member] \| Amended Term Loan [Member] \| Canadian Dollar Offered Rate [Member]
Line of Credit Facility [Line Items]
Interest rate of CORRA plus spread								6.75%
Minimum [Member]
Line of Credit Facility [Line Items]
Fixed charge coverage ratio			1
Minimum [Member] \| Amended Credit Facility [Member]
Line of Credit Facility [Line Items]
Interest rate of CORRA plus spread		1.50%						1.50%
Minimum [Member] \| Amended Credit Facility [Member] \| Canadian Overnight Repo Rate Average [Member]
Line of Credit Facility [Line Items]
Interest rate of CORRA plus spread								0.30%
Minimum [Member] \| Amended Term Loan [Member]
Line of Credit Facility [Line Items]
Interest rate of CORRA plus spread	6.75%
Minimum [Member] \| Amended Term Loan [Member] \| Canadian Overnight Repo Rate Average [Member]
Line of Credit Facility [Line Items]
Interest rate of CORRA plus spread								6.75%
Minimum [Member] \| Amended Term Loan [Member] \| Canadian Dollar Offered Rate [Member]
Line of Credit Facility [Line Items]
Interest rate of CORRA plus spread								0.32%
Arithmetic Average [Member] \| Amended Term Loan [Member] \| Canadian Overnight Repo Rate Average [Member]
Line of Credit Facility [Line Items]
Interest rate of CORRA plus spread								7.00%
Arithmetic Average [Member] \| Amended Term Loan [Member] \| Canadian Dollar Offered Rate [Member]
Line of Credit Facility [Line Items]
Interest rate of CORRA plus spread								7.75%