INDUSTRY SEGMENT INFORMATION (Details) $ in Thousands	3 Months Ended
Mar. 30, 2019 USD ($) segment company item	Mar. 31, 2018 USD ($)	Dec. 29, 2018 USD ($)
INDUSTRY SEGMENT INFORMATION
Number of industry groups in which the entity operates \| item	2
Number of reportable segments \| segment	2
Number of companies that comprise TMC \| company	3
Revenues from external customers	$ 22,528	$ 23,410
Depreciation, depletion and amortization	519	405
Operating income (loss)	12,375	(7,523)
Segment assets	90,609	75,703	$ 75,703
Capital expenditures	63	411
Held for Sale
INDUSTRY SEGMENT INFORMATION
Segment assets		24,036
Corporate, Non-Segment [Member]
INDUSTRY SEGMENT INFORMATION
Revenues from external customers	11	4
Depreciation, depletion and amortization	13	11
Operating income (loss)	(1,567)	(1,024)
Segment assets	41,873	3,346
Capital expenditures		51
Concrete Aggregates and Construction Supplies [Member]
INDUSTRY SEGMENT INFORMATION
Revenues from external customers	1,554	1,601
Depreciation, depletion and amortization	52	85
Operating income (loss)	14,044	(7,252)
Segment assets	11,760	11,315
Capital expenditures		62
Doors [Member]
INDUSTRY SEGMENT INFORMATION
Revenues from external customers	4,242	4,296
Depreciation, depletion and amortization	43	40
Operating income (loss)	379	438
Segment assets	6,805	8,003
Capital expenditures	19	33
Heating and Cooling [Member]
INDUSTRY SEGMENT INFORMATION
Revenues from external customers	10,345	10,993
Depreciation, depletion and amortization	303	162
Operating income (loss)	(216)	571
Segment assets	18,019	19,668
Capital expenditures	44	200
Evaporative Cooling [Member]
INDUSTRY SEGMENT INFORMATION
Revenues from external customers	6,376	6,516
Depreciation, depletion and amortization	107	107
Operating income (loss)	(265)	(256)
Segment assets	12,152	9,335
Capital expenditures		65
Construction Products [Member]
INDUSTRY SEGMENT INFORMATION
Revenues from external customers	5,796	5,897
Depreciation, depletion and amortization	96	125
Operating income (loss)	14,423	(6,814)
Segment assets	18,565	19,318
Capital expenditures	19	95
Heating Ventilation and Air Conditioning Products [Member]
INDUSTRY SEGMENT INFORMATION
Revenues from external customers	16,720	17,509
Depreciation, depletion and amortization	411	269
Operating income (loss)	(481)	315
Segment assets	30,171	29,003
Capital expenditures	$ 44	$ 265

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