SHAREHOLDERS' DEFICIT (Changes in Shareholders' Deficit) (Details) - USD ($) $ in Millions	3 Months Ended				6 Months Ended
	Dec. 29, 2021	Sep. 29, 2021	Dec. 23, 2020	Sep. 23, 2020	Dec. 29, 2021	Dec. 23, 2020
Increase (Decrease) in Stockholders' Deficit [Roll Forward]
Beginning balance	$ (325.5)	$ (303.3)	$ (465.1)	$ (479.1)	$ (303.3)	$ (479.1)
Net income	27.6	13.2	12.0	10.7	40.8	22.7
Other comprehensive income (loss)	(0.1)	(0.4)	0.5	0.3	(0.5)	0.8
Dividends	0.0	0.0	0.0	0.0
Stock-based compensation	5.6	4.3	3.0	3.9
Purchases of treasury stock	(35.1)	(39.6)	0.0	(3.9)
Issuances of treasury stock	0.1	0.3	5.5	3.0
Ending balance	(327.4)	(325.5)	(444.1)	(465.1)	(327.4)	(444.1)
Common Stock [Member]
Increase (Decrease) in Stockholders' Deficit [Roll Forward]
Beginning balance	7.0	7.0	7.0	7.0	7.0	7.0
Net income	0.0	0.0	0.0	0.0
Other comprehensive income (loss)	0.0	0.0	0.0	0.0
Dividends	0.0	0.0	0.0	0.0
Stock-based compensation	0.0	0.0	0.0	0.0
Purchases of treasury stock	0.0	0.0	0.0	0.0
Issuances of treasury stock	0.0	0.0	0.0	0.0
Ending balance	7.0	7.0	7.0	7.0	7.0	7.0
Additional Paid-in Capital [Member]
Increase (Decrease) in Stockholders' Deficit [Roll Forward]
Beginning balance	679.4	685.4	663.2	669.4	685.4	669.4
Net income	0.0	0.0	0.0	0.0
Other comprehensive income (loss)	0.0	0.0	0.0	0.0
Dividends	0.0	0.0	0.0	0.0
Stock-based compensation	5.6	4.3	3.0	3.9
Purchases of treasury stock	0.0	(2.0)	0.0	(1.1)
Issuances of treasury stock	(1.3)	(8.3)	1.2	(9.0)
Ending balance	683.7	679.4	667.4	663.2	683.7	667.4
Accumulated Deficit [Member]
Increase (Decrease) in Stockholders' Deficit [Roll Forward]
Beginning balance	(252.9)	(266.1)	(386.8)	(397.5)	(266.1)	(397.5)
Net income	27.6	13.2	12.0	10.7
Other comprehensive income (loss)	0.0	0.0	0.0	0.0
Dividends	0.0	0.0	0.0	0.0
Stock-based compensation	0.0	0.0	0.0	0.0
Purchases of treasury stock	0.0	0.0	0.0	0.0
Issuances of treasury stock	0.0	0.0	0.0	0.0
Ending balance	(225.3)	(252.9)	(374.8)	(386.8)	(225.3)	(374.8)
Treasury Stock [Member]
Increase (Decrease) in Stockholders' Deficit [Roll Forward]
Beginning balance	(753.9)	(724.9)	(742.6)	(751.8)	(724.9)	(751.8)
Net income	0.0	0.0	0.0	0.0
Other comprehensive income (loss)	0.0	0.0	0.0	0.0
Dividends	0.0	0.0	0.0	0.0
Stock-based compensation	0.0	0.0	0.0	0.0
Purchases of treasury stock	(35.1)	(37.6)	0.0	(2.8)
Issuances of treasury stock	1.4	8.6	4.3	12.0
Ending balance	(787.6)	(753.9)	(738.3)	(742.6)	(787.6)	(738.3)
Accumulated Other Comprehensive Loss [Member]
Increase (Decrease) in Stockholders' Deficit [Roll Forward]
Beginning balance	(5.1)	(4.7)	(5.9)	(6.2)	(4.7)	(6.2)
Net income	0.0	0.0	0.0	0.0
Other comprehensive income (loss)	(0.1)	(0.4)	0.5	0.3
Dividends	0.0	0.0	0.0	0.0
Stock-based compensation	0.0	0.0	0.0	0.0
Purchases of treasury stock	0.0	0.0	0.0	0.0
Issuances of treasury stock	0.0	0.0	0.0	0.0
Ending balance	$ (5.2)	$ (5.1)	$ (5.4)	$ (5.9)	$ (5.2)	$ (5.4)