RESTRUCTURING ACTIVITIES (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended		25 Months Ended
	Feb. 22, 2015	Feb. 23, 2014	Feb. 22, 2015	Feb. 23, 2014	Feb. 22, 2015
SCAE Plan
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Approved Cost					$ 343.0
Restructuring and Related Cost, Expected Cost	232.0		232.0		232.0
Restructuring and Related Cost, Incurred Cost	18.3	23.5	56.8	38.1
Restructuring And Related Cost Expected Cash Outflows	11.0		28.4		160.1
Restructuring And Related Cost Expected Noncash Charges	7.3		28.4		71.9
Restructuring And Related Cost Incurred Cash Outflows					117.5
Restructuring And Related Cost Incurred Noncash Charges					51.4
Acquisition Related Restructuring
Restructuring Cost and Reserve [Line Items]
Restructured and related cost incurred to date	23.7		23.7		23.7
Acquisition Related Restructuring | Consumer Foods
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost		2.4	0.3	5.7
Restructured and related cost incurred to date	21.2		21.2		21.2
Acquisition Related Restructuring | Corporate
Restructuring Cost and Reserve [Line Items]
Restructured and related cost incurred to date	2.5		2.5		2.5
Ralcorp Pre-acquisition Restructuring
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost		0.5		3.1
Restructuring And Related Cost Expected Cash Outflows	1.9
Restructuring And Related Cost Expected Noncash Charges	1.8
Restructured and related cost incurred to date	3.7		3.7		3.7
Ralcorp Pre-acquisition Restructuring | Corporate
Restructuring Cost and Reserve [Line Items]
Restructured and related cost incurred to date	0.2		0.2		0.2
Ralcorp Pre-acquisition Restructuring | Private Brands
Restructuring Cost and Reserve [Line Items]
Restructured and related cost incurred to date	$ 3.5		$ 3.5		$ 3.5