Net Sales by Geography (Details) - USD ($) $ in Millions		12 Months Ended
		Apr. 30, 2020	Apr. 30, 2019	Apr. 30, 2018
Disaggregation of Revenue [Line Items]
Net sales		$ 3,363	$ 3,324	$ 3,248
United States
Disaggregation of Revenue [Line Items]
Net sales		1,690	1,563	1,529
Developed International [Member]
Disaggregation of Revenue [Line Items]
Net sales	[1]	901	917	908
Emerging [Member]
Disaggregation of Revenue [Line Items]
Net sales	[2]	572	597	575
Travel Retail [Member]
Disaggregation of Revenue [Line Items]
Net sales	[3]	125	140	139
Non-branded and bulk [Member]
Disaggregation of Revenue [Line Items]
Net sales	[4]	$ 75	$ 107	$ 97

[1] Represents net sales of branded products to “advanced economies” as defined by the International Monetary Fund (IMF), excluding the United States. Our largest developed international markets are the United Kingdom, Germany, Australia, France, Japan, and Canada.

[2] Represents net sales of branded products to “emerging and developing economies” as defined by the IMF. Our largest emerging markets are Mexico, Poland, and Russia.

[3] Represents net sales of branded products to global duty-free customers, other travel retail customers, and the U.S. military regardless of customer location.

[4] Includes net sales of used barrels, bulk whiskey and wine, and contract bottling regardless of customer location.