Restructuring (Tables)

12 Months Ended

Apr. 30, 2014

Restructuring [Abstract]

Restructuring and related charges

	Long-Lived Asset Charges		Employee Separation		Site Preparation and Equipment Relocation		Production Start-up		Other Costs		Total
Total expected restructuring charge	$	102.8	$	63.8	$	45.4	$	42.8	$	10.2	$	265.0
Balance at May 1, 2011	$	—	$	10.2	$	—	$	—	$	—	$	10.2
Charge to expense		34.2		20.4		13.0		10.6		2.9		81.1
Cash payments		—		(13.8)		(13.0)		(10.6)		(2.9)		(40.3)
Noncash utilization		(34.2)		(8.0)		—		—		—		(42.2)
Balance at April 30, 2012	$	—	$	8.8	$	—	$	—	$	—	$	8.8
Charge to expense		8.2		3.4		13.4		10.8		3.0		38.8
Cash payments		—		(4.5)		(13.4)		(10.8)		(3.0)		(31.7)
Noncash utilization		(8.2)		—		—		—		—		(8.2)
Balance at April 30, 2013	$	—	$	7.7	$	—	$	—	$	—	$	7.7
Charge to expense		2.7		2.6		7.2		7.2		1.1		20.8
Cash payments		—		(8.4)		(7.2)		(7.2)		(1.1)		(23.9)
Noncash utilization		(2.7)		(0.2)		—		—		—		(2.9)
Balance at April 30, 2014	$	—	$	1.7	$	—	$	—	$	—	$	1.7
Remaining expected restructuring charge	$	0.2	$	0.3	$	5.2	$	9.0	$	1.9	$	16.6