ASSETS ACQUISITIONS - GFP (Details) - USD ($)		3 Months Ended	6 Months Ended
	Jun. 03, 2019	Jun. 29, 2019	Jun. 29, 2019	Jun. 30, 2019	Dec. 29, 2018
Business Acquisition [Line Items]
Goodwill		$ 5,551,000	$ 5,551,000		$ 1,000,000
American Wheatley HVAC And Global Flow Products
Business Acquisition [Line Items]
Purchase price	$ 13,019,000
Estimated working capital adjustment	586,000
Consideration paid in cash	12,163,000
Contingent liability	4,300,000
Accrual For Earn Out Agreement Achievement Of Growth Targets				$ 1,516,000
Trade receivables	1,905,000
Inventory	1,468,000
Property and equipment	2,897,000
Other assets	346,000
Intangibles	4,626,000
Goodwill	3,153,000
Retained liabilities	$ 1,375,000
American Wheatley HVAC And Global Flow Products | Minimum [Member]
Business Acquisition [Line Items]
Earn out agreement, achievement of growth targets period	24 months
American Wheatley HVAC And Global Flow Products | Maximum [Member]
Business Acquisition [Line Items]
Earn out agreement, achievement of growth targets period	36 months
Selling and administrative expense | American Wheatley HVAC And Global Flow Products
Business Acquisition [Line Items]
Transaction costs		$ 1,059,000	$ 1,101,000