Represents collateral to be remitted to mortgage company after amendment of mortgage.

No definition available.

Name:	bxc_AggregateAdditionalPrepayment
Namespace Prefix:	bxc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

It represents information about cash released under mortgage.

+ References

No definition available.

+ Details

Name:	bxc_CashReleasedUnderMortgage
Namespace Prefix:	bxc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents collateral to be remitted to borrower after amendment of mortgage.

+ References

No definition available.

+ Details

Name:	bxc_CashRemainingInCollateralAccount
Namespace Prefix:	bxc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of financing cost capitalized during the period.

+ References

No definition available.

+ Details

Name:	bxc_FinancingCostsCapitalized
Namespace Prefix:	bxc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the funds expected to be transferred as collateral for mortgage loans over the next 12 months.

+ References

No definition available.

+ Details

Name:	bxc_FundsTransferredAsCollateralForMortgageLoans
Namespace Prefix:	bxc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Represents mortgage loan secured by number of distribution facilities

+ References

No definition available.

+ Details

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

- Definition

Represents mortgage loan term period.

+ References

No definition available.

+ Details

Name:	bxc_MortgageLoanTerm
Namespace Prefix:	bxc_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date after deducting unamortized discount or premiums (if any), which had initial maturities beyond one year or beyond the normal operating cycle, if longer.

+ References

No definition available.

+ Details

Name:	bxc_MortgageRepaymentsNet
Namespace Prefix:	bxc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date before deducting unamortized discount or premiums (if any). May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer.

+ References

No definition available.

+ Details

Name:	bxc_MortgageRepaymentsOfPrincipalTotal
Namespace Prefix:	bxc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Represents prepayments of indebtedness under the mortgage.

+ References

No definition available.

+ Details

Name:	bxc_PrepaymentsOfIndebtednessUnderMortgage
Namespace Prefix:	bxc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Represents the proceeds from sale of distribution facilities.

+ References

No definition available.

+ Details

Name:	bxc_ProceedsFromSaleOfDistributionFacilities
Namespace Prefix:	bxc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

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

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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

- Details

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

- Definition

The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 1A

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28541-108399

Reference 2: 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=6584090&loc=d3e28878-108400

+ Details

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

- Definition

Amount of cash outflow associated with funds that are not available for withdrawal or use (such as funds held in escrow) and are associated with underlying transactions that are classified as investing activities.

+ References

No definition available.

+ Details

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

Mortgage (Detail Textuals) (Mortgage, USD $) In Millions, unless otherwise specified	3 Months Ended				6 Months Ended
	Jul. 05, 2014	Apr. 05, 2014	Jan. 08, 2014	Sep. 28, 2013	Jul. 05, 2014 Facility	Jan. 04, 2014	Sep. 19, 2012
Mortgage
Debt Instrument [Line Items]
Mortgage loan term					10 years
Distribution facilities					49
Mortgage interest rate	6.35%				6.35%
Financing costs capitalized					$ 3.4
Unamortized debt discount balance	1.5				1.5	1.6
Mortgage loan balance	178.7				178.7	186.9
Mortgage loan balance net of unamortized debt discount	177.2				177.2	185.3
Payment of indebtedness under the mortgage							11.8
Collateral to be remitted to mortgage company after amendment of mortgage							10.0
Collateral to be remitted to borrower after amendment of mortgage							10.0
Funds transferred as collateral in next twelve months							12.2
Increase in restricted cash			1.9	8.4
Amount released to pay for usual and customary operating expenses	3.0	3.1
Proceeds from sale of closed facility	$ 6.9