| Schedule of Segment Reporting Information, by Segment [Table Text Block] |
| | | Thirteen Weeks Ended | | | Twenty-Six Weeks Ended | |
| | | November 27, 2022 | | | November 28, 2021 | | | November 27, 2022 | | | November 28, 2021 | |
| Net sales | | | | | | | | | | | | | | | | |
| Grocery & Snacks | | $ | 1,349.9 | | | $ | 1,264.5 | | | $ | 2,538.2 | | | $ | 2,339.6 | |
| Refrigerated & Frozen | | | 1,421.5 | | | | 1,285.9 | | | | 2,629.1 | | | | 2,387.7 | |
| International | | | 258.7 | | | | 262.2 | | | | 492.2 | | | | 498.8 | |
| Foodservice | | | 282.8 | | | | 246.3 | | | | 557.7 | | | | 486.1 | |
| Total net sales | | $ | 3,312.9 | | | $ | 3,058.9 | | | $ | 6,217.2 | | | $ | 5,712.2 | |
| Operating profit | | | | | | | | | | | | | | | | |
| Grocery & Snacks | | $ | 340.4 | | | $ | 249.2 | | | $ | 590.8 | | | $ | 465.1 | |
| Refrigerated & Frozen | | | 250.3 | | | | 168.3 | | | | 34.0 | | | | 325.9 | |
| International | | | 36.9 | | | | 37.1 | | | | 63.8 | | | | 71.2 | |
| Foodservice | | | 28.5 | | | | 13.8 | | | | 29.7 | | | | 34.1 | |
| Total operating profit | | $ | 656.1 | | | $ | 468.4 | | | $ | 718.3 | | | $ | 896.3 | |
| Equity method investment earnings | | | 49.3 | | | | 29.5 | | | | 98.5 | | | | 49.7 | |
| General corporate expense | | | 106.5 | | | | 59.0 | | | | 190.0 | | | | 123.6 | |
| Pension and postretirement non-service income | | | (6.1 | ) | | | (16.1 | ) | | | (12.2 | ) | | | (32.2 | ) |
| Interest expense, net | | | 100.3 | | | | 94.9 | | | | 197.4 | | | | 189.1 | |
| Income tax expense | | | 122.5 | | | | 84.2 | | | | 136.9 | | | | 153.9 | |
| Net income | | $ | 382.2 | | | $ | 275.9 | | | $ | 304.7 | | | $ | 511.6 | |
| Less: Net income attributable to noncontrolling interests | | | 0.3 | | | | 0.4 | | | | 0.3 | | | | 0.7 | |
| Net income attributable to Conagra Brands, Inc. | | $ | 381.9 | | | $ | 275.5 | | | $ | 304.4 | | | $ | 510.9 | |
| | | Thirteen Weeks Ended | | | Twenty-Six Weeks Ended | |
| | | November 27, 2022 | | | November 28, 2021 | | | November 27, 2022 | | | November 28, 2021 | |
| Frozen | | $ | 1,157.5 | | | $ | 1,073.1 | | | $ | 2,165.9 | | | $ | 1,993.5 | |
| Staples | | | | | | | | | | | | | | | | |
| Other shelf-stable | | | 758.4 | | | | 724.6 | | | | 1,448.5 | | | | 1,366.2 | |
| Refrigerated | | | 264.0 | | | | 212.8 | | | | 463.2 | | | | 394.2 | |
| Snacks | | | 591.5 | | | | 539.9 | | | | 1,089.7 | | | | 973.4 | |
| Foodservice | | | 282.8 | | | | 246.3 | | | | 557.7 | | | | 486.1 | |
| International | | | 258.7 | | | | 262.2 | | | | 492.2 | | | | 498.8 | |
| Total net sales | | $ | 3,312.9 | | | $ | 3,058.9 | | | $ | 6,217.2 | | | $ | 5,712.2 | |
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| Allocation of Net Derivative Gains (Losses) from Economic Hedges to Operating Results of Reporting Segments [Table Text Block] |
| | | Thirteen Weeks Ended | | | Twenty-Six Weeks Ended | |
| | | November 27, 2022 | | | November 28, 2021 | | | November 27, 2022 | | | November 28, 2021 | |
| Gross derivative gains incurred | | $ | 5.2 | | | $ | 7.0 | | | $ | 14.7 | | | $ | 17.2 | |
| Less: Net derivative gains allocated to reporting segments | | | 7.6 | | | | 8.8 | | | | 16.6 | | | | 13.8 | |
| Net derivative gains (losses) recognized in general corporate expenses | | $ | (2.4 | ) | | $ | (1.8 | ) | | $ | (1.9 | ) | | $ | 3.4 | |
| Net derivative gains allocated to Grocery & Snacks | | $ | 2.5 | | | $ | 4.7 | | | $ | 7.5 | | | $ | 7.9 | |
| Net derivative gains allocated to Refrigerated & Frozen | | | 4.3 | | | | 4.6 | | | | 7.6 | | | | 9.3 | |
| Net derivative gains (losses) allocated to International | | | 0.6 | | | | (0.7 | ) | | | 0.7 | | | | (3.9 | ) |
| Net derivative gains allocated to Foodservice | | | 0.2 | | | | 0.2 | | | | 0.8 | | | | 0.5 | |
| Net derivative gains included in segment operating profit | | $ | 7.6 | | | $ | 8.8 | | | $ | 16.6 | | | $ | 13.8 | |
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