GOODWILL AND AMORTIZABLE INTANGIBLE ASSETS - Goodwill (Details) - USD ($)	12 Months Ended
Dec. 30, 2017	Dec. 31, 2016
Goodwill
Goodwill	$ 7,229,000	$ 7,229,000
Goodwill impairment charges recognized	0	0
Changes recorded in value of goodwill	0	0
Amortization expense	0	$ 21,000
Concrete Aggregates and Construction Supplies [Member]
Goodwill
Goodwill	6,229,000
Doors [Member]
Goodwill
Goodwill	$ 1,000,000

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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-Publisher FASB
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of increase (decrease) of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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