SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Schedule of Accumulated Balances for Each Component of Other Comprehensive Income (Loss), Net of Tax (Details) - USD ($) $ in Millions	9 Months Ended
	Feb. 25, 2018	May 28, 2017
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated balances	$ 3,809.5	$ 4,077.8
Currency translation losses, net of reclassification adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated balances	(73.0)	(98.6)
Derivative adjustments, net of reclassification adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated balances	0.5	(1.1)
Unrealized gains (losses) on available-for-sale securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated balances	0.8	(0.3)
Pension and post-employment benefit obligations, net of reclassification adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated balances	(103.8)	(112.9)
Accumulated other comprehensive loss
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated balances	(175.5)	(212.9)
Retained earnings
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated balances	4,758.8	$ 4,247.0
Accounting Standards Update 2018-02
Accumulated Other Comprehensive Income (Loss) [Line Items]
Adoption of ASU 2018-02	0.0
Accounting Standards Update 2018-02 | Accumulated other comprehensive loss
Accumulated Other Comprehensive Income (Loss) [Line Items]
Adoption of ASU 2018-02	(17.4)
Accounting Standards Update 2018-02 | Retained earnings
Accumulated Other Comprehensive Income (Loss) [Line Items]
Adoption of ASU 2018-02	$ 17.4