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Face (par) amount of debt instrument at time of issuance.

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The cash outflow for the extinguishment of long-term borrowing, with the highest claim on the assets of the entity in case of bankruptcy or liquidation, before its maturity.

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Amount of cash paid for interest. Includes, but is not limited to, payment to settle zero-coupon bond attributable to accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount.

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Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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The cash outflow for a borrowing supported by a written promise to pay an obligation.

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LONG-TERM DEBT - Narrative (Details) - USD ($)		3 Months Ended					12 Months Ended
LONG-TERM DEBT - Narrative (Details) - USD ($)	Nov. 09, 2016	Feb. 26, 2017	Aug. 28, 2016	Feb. 28, 2016	Nov. 29, 2015	Aug. 24, 2014	May 28, 2017	May 29, 2016	May 31, 2015
Debt Instrument [Line Items]
Repayments of long-term debt							$ 1,064,500,000	$ 2,523,200,000	$ 1,491,400,000
Net loss on early retirement of debt				$ 23,900,000			93,300,000	23,900,000	24,600,000
Issuance of term loans				600,000,000.0
Interest paid from continuing operations							$ 223,700,000	$ 322,000,000	333,500,000
Senior notes
Debt Instrument [Line Items]
Net loss on early retirement of debt	$ 60,600,000
5.819% senior notes due 2017 \| Senior notes
Debt Instrument [Line Items]
Aggregate principal amount of notes exchanged	250,200,000
7.0% senior notes due 2019 \| Senior notes
Debt Instrument [Line Items]
Aggregate principal amount of notes exchanged	86,900,000
1.9% senior notes due 2018 \| Senior notes
Debt Instrument [Line Items]
Aggregate principal amount of notes exchanged	880,400,000
2.1% senior notes due 2018 \| Senior notes
Debt Instrument [Line Items]
Aggregate principal amount of notes exchanged	154,900,000
4.95% senior notes due 2020 \| Senior notes
Debt Instrument [Line Items]
Aggregate principal amount of notes exchanged	$ 71,100,000
Senior notes due 2043
Debt Instrument [Line Items]
Repayments of long-term debt									200,000,000
Senior notes due 2019
Debt Instrument [Line Items]
Repayments of long-term debt									25,000,000
Senior notes due 2023
Debt Instrument [Line Items]
Repayments of long-term debt									225,000,000
Senior notes due 2018
Debt Instrument [Line Items]
Repayments of long-term debt									25,000,000
Senior notes due 2017
Debt Instrument [Line Items]
Repayments of long-term debt									25,000,000
Senior notes due 2023, 2043, 2019, 2018, and 2017
Debt Instrument [Line Items]
Net loss on early retirement of debt									16,300,000
Floating rate notes
Debt Instrument [Line Items]
Floating rate notes issued									$ 550,000,000
Floating rate notes \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate								0.37%
Senior notes
Debt Instrument [Line Items]
Net loss on early retirement of debt		$ 32,700,000
Senior notes \| 5.819% senior notes due 2017
Debt Instrument [Line Items]
Repayments of long-term debt		$ 224,800,000
Stated interest rate	5.819%	5.819%
Senior notes \| 7.0% senior notes due 2019
Debt Instrument [Line Items]
Repayments of long-term debt		$ 248,200,000
Stated interest rate	7.00%	7.00%
Senior notes \| 1.9% senior notes due 2018
Debt Instrument [Line Items]
Stated interest rate	1.90%
Senior notes \| 2.1% senior notes due 2018
Debt Instrument [Line Items]
Stated interest rate	2.10%
Senior notes \| 4.95% senior notes due 2020
Debt Instrument [Line Items]
Stated interest rate	4.95%
Senior notes \| Senior notes due 2043
Debt Instrument [Line Items]
Aggregate principal amount of senior notes repurchased				560,300,000
Senior notes \| Senior notes due 2039
Debt Instrument [Line Items]
Aggregate principal amount of senior notes repurchased				341,800,000
Senior notes \| Senior notes due 2019
Debt Instrument [Line Items]
Aggregate principal amount of senior notes repurchased				139,900,000
Senior notes \| Senior notes due 2026
Debt Instrument [Line Items]
Aggregate principal amount of senior notes repurchased				110,000,000
Senior notes \| Senior notes due 2020
Debt Instrument [Line Items]
Aggregate principal amount of senior notes repurchased				85,000,000
Senior notes \| Senior notes due 2023
Debt Instrument [Line Items]
Aggregate principal amount of senior notes repurchased				$ 163,000,000
Senior notes \| 1.30% senior notes
Debt Instrument [Line Items]
Stated interest rate				1.30%
Principal balance repaid on senior notes				$ 750,000,000
Senior notes \| 1.35% senior notes
Debt Instrument [Line Items]
Repayments of long-term debt					$ 250,000,000
Stated interest rate					1.35%
Floating rate notes
Debt Instrument [Line Items]
Principal balance repaid on floating rate notes			$ 550,000,000
Floating rate notes \| Floating rate notes \| LIBOR
Debt Instrument [Line Items]
Stated interest rate									0.37%
Unsecured term loan facility \| The Term Loan Facility
Debt Instrument [Line Items]
Net loss on early retirement of debt						$ 8,300,000
Term Loan Facility, borrowings repaid						$ 900,000,000.0
Unsecured term loan facility \| The Term Loan Facility \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate						1.75%
Ralcorp
Debt Instrument [Line Items]
Net loss on early retirement of debt								$ 5,400,000
Repayment of senior notes issued by Ralcorp				$ 33,900,000				$ 33,900,000
Ralcorp \| Senior notes \| Senior notes due 2039
Debt Instrument [Line Items]
Stated interest rate								6.625%
Repayment of senior notes issued by Ralcorp								$ 16,700,000
Ralcorp \| Senior notes \| Senior notes due 2020
Debt Instrument [Line Items]
Stated interest rate								4.95%
Repayment of senior notes issued by Ralcorp								$ 17,200,000
Spinoff \| Lamb Weston
Debt Instrument [Line Items]
Lamb Weston notes	$ 1,540,000,000