DISCONTINUED OPERATIONS AND OTHER DIVESTITURES - Private Brands Operations (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
Aug. 27, 2017	Aug. 28, 2016	Feb. 01, 2016
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
After-tax (loss) income	$ (0.3)	$ 87.8
Private Brands \| Discontinued operations, disposed of by sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash price for disposition			$ 2,600.0
After-tax (loss) income	(0.1)	1.5
Pre-tax gain	0.1	0.8
TreeHouse Foods, Inc. \| Buyer of Private Brands Operations \| Transition services agreement
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income from transition services agreement	$ 1.7	$ 6.1

Amount before tax of income (loss) from operations classified as a discontinued operation attributable to the parent. Excludes gain (loss) on disposal and provision for gain (loss) until its disposal.

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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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