Mortgage (Details) (USD $) In Thousands, unless otherwise specified	Jan. 04, 2014
Mortgage outstanding principal balance
2014	$ 2,761
2015	2,744
2016	181,438
2017
2018
Thereafter
Total	$ 186,943

- Details

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

- Definition

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

Represents 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

Represents 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

Represents 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

Represents 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

Represents 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

Represents 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