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DISCONTINUED OPERATIONS - Financial Results of Instaff (Details) - USD ($)	3 Months Ended								12 Months Ended
	Dec. 26, 2021	Sep. 26, 2021	Jun. 27, 2021	Mar. 28, 2021	Dec. 27, 2020	Sep. 27, 2020	Jun. 28, 2020	Mar. 29, 2020	Dec. 26, 2021	Dec. 27, 2020	Dec. 29, 2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income from discontinued operations, net of tax	$ 990,482	$ 930,129	$ 807,612	$ 923,380	$ 1,125,219	$ 938,050	$ 641,525	$ 808,561	$ 3,651,603	$ 3,513,355	$ 3,606,159
Instaff \| Discontinued Operations, Held-for-sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revenue									71,292,000	70,765,000	74,549,000
Cost of services									60,948,000	60,585,000	63,694,000
Gross profit									10,344,000	10,180,000	10,855,000
Selling expenses									5,684,000	5,315,000	5,977,000
Depreciation									90,000	99,000	102,000
Income from operations of discontinued operations before taxes									4,570,000	4,766,000	4,776,000
Income taxes									(918,000)	(1,253,000)	(1,170,000)
Income from discontinued operations, net of tax									$ 3,652,000	$ 3,513,000	$ 3,606,000