Other Comprehensive Income (Details) - USD ($) $ in Millions		3 Months Ended
		Jul. 31, 2016	Jul. 31, 2015
Before Tax:
Net other comprehensive income (loss)		$ (44)	$ 8
Tax Effect:
Net other comprehensive income (loss)		(8)	(12)
Net of Tax:
Net other comprehensive income (loss)		(52)	(4)
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Before Tax:
Net gain (loss)		(68)	(23)
Reclassification to earnings		0	0
Net other comprehensive income (loss)		(68)	(23)
Tax Effect:
Net gain (loss)		1	(1)
Reclassification to earnings		0	0
Net other comprehensive income (loss)		1	(1)
Net of Tax:
Net gain (loss)		(67)	(24)
Reclassification to earnings		0	0
Net other comprehensive income (loss)		(67)	(24)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
Before Tax:
Net gain (loss)		29	37
Reclassification to earnings	[1]	(10)	(13)
Net other comprehensive income (loss)		19	24
Tax Effect:
Net gain (loss)		(11)	(12)
Reclassification to earnings	[1]	4	4
Net other comprehensive income (loss)		(7)	(8)
Net of Tax:
Net gain (loss)		18	25
Reclassification to earnings	[1]	(6)	(9)
Net other comprehensive income (loss)		12	16
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Before Tax:
Net gain (loss)		0	0
Reclassification to earnings	[2]	5	7
Net other comprehensive income (loss)		5	7
Tax Effect:
Net gain (loss)		0	0
Reclassification to earnings	[2]	(2)	(3)
Net other comprehensive income (loss)		(2)	(3)
Net of Tax:
Net gain (loss)		0	0
Reclassification to earnings	[2]	3	4
Net other comprehensive income (loss)		$ 3	$ 4

[1] Pre-tax amount is classified as net sales in the accompanying consolidated statements of operations.

[2] Pre-tax amount is a component of pension and other postretirement benefit expense (as shown in Note 7, except for amounts related to non-U.S. benefit plans, about which no information is presented in Note 7 due to immateriality).