Reportable Segment (Details 2) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Oct. 31, 2018	Oct. 31, 2017	Oct. 31, 2018	Oct. 31, 2017
Product category information [Line Items]
Net sales		$ 2,021.5	$ 1,923.6	$ 3,924.0	$ 3,672.5
Percent of product sales attributable to primary reportable segment				75.00%
U.S. Retail Coffee [Member]
Product category information [Line Items]
Net sales		544.9	551.4	$ 1,034.4	1,030.8
U.S. Retail Coffee [Member] | Coffee [Member]
Product category information [Line Items]
Net sales	[1]	635.5	649.3	1,213.8	1,221.6
U.S. Retail Consumer Foods [Member]
Product category information [Line Items]
Net sales		461.9	527.8	945.2	1,015.7
U.S. Retail Consumer Foods [Member] | Peanut butter [Member]
Product category information [Line Items]
Net sales	[1]	186.9	184.4	386.1	384.9
U.S. Retail Consumer Foods [Member] | Fruit spreads [Member]
Product category information [Line Items]
Net sales	[1]	83.0	90.5	168.6	178.1
U.S. Retail Consumer Foods [Member] | Frozen handheld [Member]
Product category information [Line Items]
Net sales	[1]	78.7	69.0	143.2	119.0
U.S. Retail Consumer Foods [Member] | Baking mixes and ingredients [Member]
Product category information [Line Items]
Net sales	[1]	58.4	128.4	142.7	220.2
U.S. Retail Consumer Foods [Member] | Shortening and oils [Member]
Product category information [Line Items]
Net sales	[1]	79.3	77.7	132.2	134.0
U.S. Retail Consumer Foods [Member] | Juices and beverages [Member]
Product category information [Line Items]
Net sales	[1]	33.9	37.3	66.1	74.4
U.S. Retail Pet Foods [Member]
Product category information [Line Items]
Net sales		728.1	551.1	1,399.3	1,071.8
U.S. Retail Pet Foods [Member] | Dog food [Member]
Product category information [Line Items]
Net sales	[1]	334.9	195.7	643.4	384.4
U.S. Retail Pet Foods [Member] | Cat food [Member]
Product category information [Line Items]
Net sales	[1]	207.3	177.8	396.3	343.6
U.S. Retail Pet Foods [Member] | Pet snacks [Member]
Product category information [Line Items]
Net sales	[1]	201.9	192.6	389.7	373.3
International and Away From Home [Member]
Product category information [Line Items]
Net sales		286.6	293.3	545.1	554.2
International and Away From Home [Member] | Portion control [Member]
Product category information [Line Items]
Net sales	[1]	41.6	42.0	82.5	81.7
International and Away From Home [Member] | Other [Member]
Product category information [Line Items]
Net sales	[1]	$ 80.1	$ 78.9	$ 159.4	$ 157.3

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