INDUSTRY SEGMENT INFORMATION (Details) $ in Thousands	3 Months Ended
Mar. 28, 2020 USD ($) segment company	Mar. 30, 2019 USD ($)	Dec. 28, 2019 USD ($)
INDUSTRY SEGMENT INFORMATION
Number of reportable segments \| segment	3
Number of companies \| company	3
Revenues from external customers	$ 30,845	$ 22,528
Depreciation and amortization	513	519
Operating income (loss)	134	12,375
Segment assets	88,187	89,983	$ 89,983
Capital expenditures	26	63
Held for Sale
INDUSTRY SEGMENT INFORMATION
Segment assets	380	896
Unallocated Corporate
INDUSTRY SEGMENT INFORMATION
Revenues from external customers		11
Depreciation and amortization	61	13
Operating income (loss)	(1,845)	(1,567)
Segment assets	22,760	13,554
HVAC
INDUSTRY SEGMENT INFORMATION
Revenues from external customers	23,655	16,720
Depreciation and amortization	332	411
Operating income (loss)	2,536	(481)
Segment assets	46,250	50,822
Capital expenditures	12	44
Doors
INDUSTRY SEGMENT INFORMATION
Revenues from external customers	5,721	4,242
Depreciation and amortization	73	43
Operating income (loss)	79	379
Segment assets	11,506	14,248
Capital expenditures	14	19
Construction Materials
INDUSTRY SEGMENT INFORMATION
Revenues from external customers	1,470	1,554
Depreciation and amortization	48	52
Operating income (loss)	(636)	14,044
Segment assets	$ 7,291	$ 10,463

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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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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