Net Sales by Geography (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Oct. 31, 2019	Oct. 31, 2018	Oct. 31, 2019		Oct. 31, 2018
Disaggregation of Revenue [Line Items]
Net sales	$ 989	$ 910	$ 1,755		$ 1,676
United States [Member]
Disaggregation of Revenue [Line Items]
Net sales	506	444	880		798
Developed International [Member]
Disaggregation of Revenue [Line Items]
Net sales	248	234	453	[1]	449	[1]
Emerging [Member]
Disaggregation of Revenue [Line Items]
Net sales	173	164	306	[2]	295	[2]
Travel Retail [Member]
Disaggregation of Revenue [Line Items]
Net sales	38	38	70	[3]	76	[3]
Non-branded and bulk [Member]
Disaggregation of Revenue [Line Items]
Net sales	$ 24	$ 30	$ 46	[4]	$ 58	[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.