Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	12 Months Ended
	May 28, 2017	May 29, 2016	May 31, 2015
Net income (loss)
Pre-Tax Amount	$ 989.2	$ (1,033.6)	$ 244.0
Tax (Expense) Benefit	(341.2)	367.7	(484.8)
Net income (loss)	648.0	(665.9)	(240.8)
Unrealized derivative adjustments
Pre-Tax Amount	(1.0)	0.0	0.0
Tax (Expense) Benefit	0.4	0.0	0.0
After-Tax Amount	(0.6)	0.0	0.0
Reclassification for derivative adjustments included in net income
Pre-Tax Amount	(0.2)	(2.1)	(0.5)
Tax (Expense) Benefit	0.1	0.8	0.2
After-Tax Amount	(0.1)	(1.3)	(0.3)
Unrealized gains on available-for-sale securities
Pre-Tax Amount	0.5	0.1	0.7
Tax (Expense) Benefit	(0.2)	0.0	(0.3)
After-Tax Amount	0.3	0.1	0.4
Unrealized currency translation losses
Pre-Tax Amount	(13.6)	(58.9)	(145.2)
Tax (Expense) Benefit	0.2	0.0	0.0
After-Tax Amount	(13.4)	(58.9)	(145.2)
Reclassification for currency translation losses included in net income
Pre-Tax Amount	0.0	73.4	0.0
Tax (Expense) Benefit	0.0	0.0	0.0
After-Tax Amount	0.0	73.4	0.0
Unrealized pension and post-employment benefit obligations
Pre-Tax Amount	209.2	(37.7)	(94.9)
Tax (Expense) Benefit	(80.6)	14.8	36.7
After-Tax Amount	128.6	(22.9)	(58.2)
Reclassification for pension and post-employment benefit obligations included in net income
Pre-Tax Amount	10.4	(14.5)	0.8
Tax (Expense) Benefit	(4.0)	4.9	(0.3)
After-Tax Amount	6.4	(9.6)	0.5
Comprehensive income (loss)
Pre-Tax Amount	1,194.5	(1,073.3)	4.9
Tax (Expense) Benefit	(425.3)	388.2	(448.5)
After-Tax Amount	769.2	(685.1)	(443.6)
Comprehensive income attributable to noncontrolling interests
Pre-Tax Amount	12.6	7.8	4.6
Tax (Expense) Benefit	(0.7)	(0.9)	(0.4)
After-Tax Amount	11.9	6.9	4.2
Comprehensive income (loss) attributable to Conagra Brands, Inc.
Pre-Tax Amount	1,181.9	(1,081.1)	0.3
Tax (Expense) Benefit	(424.6)	389.1	(448.1)
After-Tax Amount	$ 757.3	$ (692.0)	$ (447.8)