Reportable Segments (Details 2) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Oct. 31, 2019	Oct. 31, 2018	Oct. 31, 2019	Oct. 31, 2018
Product category information [Line Items]
Net sales		$ 1,957.8	$ 2,021.5	$ 3,736.7	$ 3,924.0
Percent of product sales attributable to primary reportable segment				75.00%
U.S. Retail Pet Foods [Member]
Product category information [Line Items]
Net sales		709.9	728.1	$ 1,379.8	1,399.3
U.S. Retail Pet Foods [Member] | Dog food [Member]
Product category information [Line Items]
Net sales	[1]	302.6	334.9	598.2	643.4
U.S. Retail Pet Foods [Member] | Cat food [Member]
Product category information [Line Items]
Net sales	[1]	213.8	207.3	409.7	396.3
U.S. Retail Pet Foods [Member] | Pet snacks [Member]
Product category information [Line Items]
Net sales	[1]	210.0	201.9	403.2	389.7
U.S. Retail Coffee [Member]
Product category information [Line Items]
Net sales		543.4	544.9	1,009.1	1,034.4
U.S. Retail Coffee [Member] | Coffee [Member]
Product category information [Line Items]
Net sales	[1]	627.1	635.5	1,173.8	1,213.8
U.S. Retail Consumer Foods [Member]
Product category information [Line Items]
Net sales		426.1	461.9	828.3	945.2
U.S. Retail Consumer Foods [Member] | Peanut butter [Member]
Product category information [Line Items]
Net sales	[1]	175.4	186.9	353.3	386.1
U.S. Retail Consumer Foods [Member] | Fruit spreads [Member]
Product category information [Line Items]
Net sales	[1]	86.5	83.0	175.7	168.6
U.S. Retail Consumer Foods [Member] | Frozen handheld [Member]
Product category information [Line Items]
Net sales	[1]	93.4	78.7	164.9	143.2
U.S. Retail Consumer Foods [Member] | Shortening and oils [Member]
Product category information [Line Items]
Net sales	[1]	71.8	79.3	123.3	132.2
U.S. Retail Consumer Foods [Member] | Juices and beverages [Member]
Product category information [Line Items]
Net sales	[1]	32.4	33.9	63.6	66.1
International and Away From Home [Member]
Product category information [Line Items]
Net sales		278.4	286.6	519.5	545.1
International and Away From Home [Member] | Portion control [Member]
Product category information [Line Items]
Net sales	[1]	42.5	41.6	81.9	82.5
International and Away From Home [Member] | Baking mixes and ingredients [Member]
Product category information [Line Items]
Net sales	[1],[2]	26.0	58.4	39.7	142.7
International and Away From Home [Member] | Other [Member]
Product category information [Line Items]
Net sales	[1]	$ 76.3	$ 80.1	$ 149.4	$ 159.4

[1] The primary reportable segment generally represents at least 75 percent of total net sales for each respective product category.

[2] During the three and six months ended October 31, 2018, the primary reportable segment was U.S. Retail Consumer Foods, as the majority of the net sales within this category were related to the divested U.S. baking business. For more information, see Note 5: Divestiture.