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v3.19.1

Commitments and Contingencies (Details) | 12 Months Ended
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Dec. 29, 2018 employee Agreement
Commitments and Contingencies Disclosure [Abstract] |
Entity number of employees | 2,400
Percentages of employees represented by various labor unions | 20.00%
Number of collective bargaining agreements up for renewal, next fiscal year | Agreement | 7
Number of employees covered | 130

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- Definition Number Of Collective Bargaining Agreements Up For Renewal in Next Fiscal Year + References No definition available. + Details
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- Definition Number Of Employees Covered by Collective Bargaining Agreements Up For Renewal in Next Fiscal Year + References No definition available. + Details
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Namespace Prefix: | bxc_
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- Definition Percentage of employees represented by various labor unions. + References No definition available. + Details
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Namespace Prefix: | bxc_
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- Definition Number of persons employed by the Entity + References No definition available. + Details
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Balance Type: | na
Period Type: | instant

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- References No definition available. + Details
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