Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended
Jul. 31, 2016	Jul. 31, 2015
Statement of Comprehensive Income [Abstract]
Net income	$ 144	$ 156
Other comprehensive income (loss), net of tax:
Currency translation adjustments	(67)	(24)
Cash flow hedge adjustments	12	16
Postretirement benefits adjustments	3	4
Net other comprehensive income (loss)	(52)	(4)
Comprehensive income	$ 92	$ 152

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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