Mortgage (Details) (USD $) In Thousands, unless otherwise specified	Dec. 29, 2012
Mortgage outstanding principal balance
2013	$ 8,946
2014	2,556
2015	2,725
2016	191,753
2017
Thereafter
Total	$ 205,980

- Details

Name:	bxc_MortgageOutstandingPrincipalBalanceAbstract
Namespace Prefix:	bxc_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

This element represents the total amount of mortgage repayments of principal.

+ References

No definition available.

+ Details

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

- Definition

Portion of the mortgage balance redeemable at fixed or determinable prices and dates maturing after the fifth fiscal year following the current fiscal year.

+ References

No definition available.

+ Details

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

- Definition

Portion of the mortgage balance redeemable at fixed or determinable prices and dates maturing in the fifth fiscal year following the current fiscal year.

+ References

No definition available.

+ Details

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

- Definition

Portion of the mortgage balance redeemable at fixed or determinable prices and dates maturing in the fourth fiscal year following the current fiscal year.

+ References

No definition available.

+ Details

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

- Definition

Portion of the mortgage balance redeemable at fixed or determinable prices and dates maturing in the first year following the current fiscal year.

+ References

No definition available.

+ Details

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

- Definition

Portion of the mortgage balance redeemable at fixed or determinable prices and dates maturing in the third fiscal year following the current fiscal year.

+ References

No definition available.

+ Details

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

- Definition

Portion of the mortgage balance redeemable at fixed or determinable prices and dates maturing in second fiscal year following the current fiscal year.

+ References

No definition available.

+ Details

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