Net Sales by Geography (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jan. 31, 2020	Jan. 31, 2019	Jan. 31, 2020		Jan. 31, 2019
Disaggregation of Revenue [Line Items]
Net sales	$ 899	$ 904	$ 2,654		$ 2,580
United States [Member]
Disaggregation of Revenue [Line Items]
Net sales	416	411	1,296		1,209
Developed International [Member]
Disaggregation of Revenue [Line Items]
Net sales	263	269	716	[1]	718	[1]
Emerging [Member]
Disaggregation of Revenue [Line Items]
Net sales	171	165	477	[2]	460	[2]
Travel Retail [Member]
Disaggregation of Revenue [Line Items]
Net sales	34	33	104	[3]	109	[3]
Non-branded and bulk [Member]
Disaggregation of Revenue [Line Items]
Net sales	$ 15	$ 26	$ 61	[4]	$ 84	[4]

[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, Australia, Germany, France, and Japan.

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

[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.