Net Sales by Geography (Details) - USD ($) $ in Millions		12 Months Ended
		Apr. 30, 2019	Apr. 30, 2018	Apr. 30, 2017
Disaggregation of Revenue [Line Items]
Net sales		$ 3,324	$ 3,248	$ 2,994
UNITED STATES
Disaggregation of Revenue [Line Items]
Net sales		1,574	1,539	1,444
Developed International [Member]
Disaggregation of Revenue [Line Items]
Net sales	[1]	917	908	852
Emerging [Member]
Disaggregation of Revenue [Line Items]
Net sales	[2]	597	575	487
Travel Retail [Member]
Disaggregation of Revenue [Line Items]
Net sales	[3]	140	139	123
Non-branded and bulk [Member]
Disaggregation of Revenue [Line Items]
Net sales	[4]	$ 96	$ 87	$ 88

[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.