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DEBT AND FINANCING OBLIGATIONS - Credit Agreement (Details) - USD ($) $ in Millions		9 Months Ended
	Jun. 28, 2019	Feb. 23, 2020	Mar. 31, 2020	May 26, 2019
Debt and Financing Obligations
Total face value of debt		$ 2,239.8		$ 2,265.1
Short-term borrowings		$ 21.0		8.4
Revolving Credit Facility, November 2016 \| Secured Debt \| Revolving Credit Facility
Debt and Financing Obligations
Debt instrument, maturity date		Nov. 09, 2021
Short-term borrowings		$ 0.0	$ 495.0	7.2
Available amount		495.1
Letter of credit outstanding		4.9
Minimum borrowings during the period		0.0
Maximum borrowings during the period		$ 97.9
Average interest rate (as a percent)		3.62%
Revolving Credit Facility, November 2016 \| Secured Debt \| Revolving Credit Facility \| Federal Fund Rate
Debt and Financing Obligations
Variable interest rate spread (as a percent)		0.50%
Revolving Credit Facility, November 2016 \| Secured Debt \| Revolving Credit Facility \| One month Eurocurrency Rate
Debt and Financing Obligations
Variable interest rate spread (as a percent)		1.00%
Revolving Credit Facility, November 2016 \| Secured Debt \| Revolving Credit Facility \| Minimum \| Base Rate
Debt and Financing Obligations
Variable interest rate spread (as a percent)		0.50%
Revolving Credit Facility, November 2016 \| Secured Debt \| Revolving Credit Facility \| Minimum \| Eurocurrency rate
Debt and Financing Obligations
Variable interest rate spread (as a percent)		1.50%
Revolving Credit Facility, November 2016 \| Secured Debt \| Revolving Credit Facility \| Maximum \| Base Rate
Debt and Financing Obligations
Variable interest rate spread (as a percent)		1.25%
Revolving Credit Facility, November 2016 \| Secured Debt \| Revolving Credit Facility \| Maximum \| Eurocurrency rate
Debt and Financing Obligations
Variable interest rate spread (as a percent)		2.25%
Term Loan Facility, due 2021 \| Secured Debt
Debt and Financing Obligations
Total face value of debt		$ 281.3		$ 599.1
Term Loan Facility, due 2021 \| Secured Debt
Debt and Financing Obligations
Face amount	$ 300.0
Total face value of debt	599.1
Term Loan Facility, due 2024 \| Secured Debt
Debt and Financing Obligations
Total face value of debt	300.0	292.5
New Term Loan Facility \| Secured Debt
Debt and Financing Obligations
Increased amount in borrowing capacity	100.0
Capitalized for debt issuance costs	$ 1.0
Interest expense, net		$ 1.7
New Term Loan Facility \| Secured Debt \| Minimum \| LIBOR
Debt and Financing Obligations
Variable interest rate spread (as a percent)	1.625%
New Term Loan Facility \| Secured Debt \| Minimum \| Base Rate
Debt and Financing Obligations
Variable interest rate spread (as a percent)	0.625%
New Term Loan Facility \| Secured Debt \| Maximum \| LIBOR
Debt and Financing Obligations
Variable interest rate spread (as a percent)	2.375%
New Term Loan Facility \| Secured Debt \| Maximum \| Base Rate
Debt and Financing Obligations
Variable interest rate spread (as a percent)	1.375%