SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Adjustments from Amounts Previously Reported (Details) - USD ($) $ in Millions	6 Months Ended
	Mar. 29, 2019	Mar. 30, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cash used in investing activities	$ (34.6)	$ (55.0)
Cash, cash equivalents, and restricted cash at beginning of period	516.4	718.5
Cash, cash equivalents, and restricted cash at end of period	$ 558.9	742.3
Adjustments
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cash used in investing activities		0.1
Cash, cash equivalents, and restricted cash at beginning of period		2.3
Cash, cash equivalents, and restricted cash at end of period		2.4
As Previously Reported
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cash used in investing activities		(55.1)
Cash, cash equivalents, and restricted cash at beginning of period		716.2
Cash, cash equivalents, and restricted cash at end of period		$ 739.9