Number of facilities closed for which lease reserves were recorded.

No definition available.

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- Definition

Represents the remaining building on the Atlanta, Georgia headquarters lease.

+ References

No definition available.

+ Details

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Namespace Prefix:	bxc_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the space remittance fees payable with respect to this unoccupied space.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

Represents the unoccupied building formerly part of the Atlanta, Georgia lease on the headquarters building.

+ References

No definition available.

+ Details

Name:	bxc_UnoccupiedBuildingHeadquartersLease
Namespace Prefix:	bxc_
Data Type:	xbrli:integerItemType
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- Definition

Date which lease or group of leases is set to expire, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

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- Definition

Amount of other expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses associated with a discontinued operation or an asset retirement obligation.

+ References

Reference 1: 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=31042434&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 420

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 420

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SAB TOPIC 5.P.4(b))

-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 420

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 5.P.3)

-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140864-122747

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

-Section P

-Subsection 3, 4

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Amount of cash outflow for the allowance granted to lessee and/or direct costs incurred by lessor used to prepare the leased premises for tenant's occupancy.

+ References

No definition available.

+ Details

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

- Definition

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

+ Details

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

- Details

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- Definition

Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Carrying amount as of the balance sheet date of improvements having a life longer than one year that were made for the benefit of one or more tenants.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.1(f))

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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Restructuring Charges (Detail Textuals) (USD $)	3 Months Ended	9 Months Ended		3 Months Ended		9 Months Ended	3 Months Ended	9 Months Ended	3 Months Ended	9 Months Ended
Restructuring Charges (Detail Textuals) (USD $)	Sep. 28, 2013 Building	Sep. 28, 2013 Building	Mar. 31, 2012	Sep. 28, 2013 Selling, general, and administrative	Jun. 29, 2013 Selling, general, and administrative	Sep. 28, 2013 Selling, general, and administrative	Sep. 28, 2013 Facility Lease Obligation	Sep. 28, 2013 Facility Lease Obligation	Sep. 28, 2013 Facility Lease Obligation Selling, general, and administrative	Sep. 28, 2013 Facility Lease Obligation Selling, general, and administrative Facility
Restructuring Cost and Reserve [Line Items]
Severance charges		$ 4,703,000		$ 400,000		$ 4,700,000
Lease obligation charges	1,839,000	6,170,000					1,398,000	1,398,000	1,400,000	1,400,000
Number of facilities closed for which lease reserves were recorded										2
Other restructuring related charges				700,000	1,300,000	2,000,000
Number of unoccupied buildings	4,100
Number of occupied buildings		4,300
Space remittance fee			5,000,000
Contractually obligated tenant improvement reimbursement expense	900,000
Contractually obligated additional tenant improvement reimbursement expense payable	$ 300,000	$ 300,000
Lease expiration date		Jan. 31, 2019