OTHER COMPREHENSIVE INCOME OR LOSS - Changes in the AOCI Balance (Details) - USD ($) $ in Millions	4 Months Ended
	Jun. 20, 2020	Jun. 15, 2019
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ 2,278.1	$ 1,450.7
Other comprehensive (loss) income before reclassifications	1.2	(23.9)
Amounts reclassified from accumulated other comprehensive income	1.1	(1.2)
Tax benefit (expense)	(0.6)	6.6
Other comprehensive income (loss)	1.7	(1.9)
Ending balance	$ 1,194.9	2,054.4
Accounting standards update [Extensible List]	us-gaap:AccountingStandardsUpdate201802Member
Accumulated other comprehensive income
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ (118.5)	91.3
Ending balance	(116.8)	89.4
Interest rate swaps
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	0.0	3.4
Other comprehensive (loss) income before reclassifications	0.0	(35.7)
Amounts reclassified from accumulated other comprehensive income	0.0	(2.5)
Tax benefit (expense)	0.0	10.0
Other comprehensive income (loss)	0.0	(27.0)
Ending balance	0.0	(23.6)
Pension and Post-retirement benefit plans
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(121.7)	88.8
Other comprehensive (loss) income before reclassifications	0.0	10.1
Amounts reclassified from accumulated other comprehensive income	1.1	1.3
Tax benefit (expense)	(0.3)	(2.9)
Other comprehensive income (loss)	0.8	23.4
Ending balance	(120.9)	112.2
Other
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	3.2	(0.9)
Other comprehensive (loss) income before reclassifications	1.2	1.7
Amounts reclassified from accumulated other comprehensive income	0.0	0.0
Tax benefit (expense)	(0.3)	(0.5)
Other comprehensive income (loss)	0.9	1.7
Ending balance	$ 4.1	0.8
Adoption of new accounting standards, net of tax
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance		574.6
Adoption of new accounting standards, net of tax | Accumulated other comprehensive income
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance		16.6
Adoption of new accounting standards, net of tax | Interest rate swaps
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance		1.2
Adoption of new accounting standards, net of tax | Pension and Post-retirement benefit plans
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance		14.9
Adoption of new accounting standards, net of tax | Other
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance		$ 0.5