Net Sales by Geography (Details) - USD ($) $ in Millions		3 Months Ended
		Jul. 31, 2020	Jul. 31, 2019
Disaggregation of Revenue [Line Items]
Net sales		$ 753	$ 766
United States [Member]
Disaggregation of Revenue [Line Items]
Net sales		387	374
Developed International [Member]
Disaggregation of Revenue [Line Items]
Net sales	[1]	231	205
Emerging [Member]
Disaggregation of Revenue [Line Items]
Net sales	[2]	107	133
Travel Retail [Member]
Disaggregation of Revenue [Line Items]
Net sales	[3]	13	32
Non-branded and bulk [Member]
Disaggregation of Revenue [Line Items]
Net sales	[4]	$ 15	$ 22

[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, and France.

[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.