Derivative Financial Instruments (Tables)

6 Months Ended

Oct. 31, 2013

Derivative Financial Instruments [Abstract]

Fair value of derivative instruments

	October 31, 2013						April 30, 2013
	Other Current Assets		Other Current Liabilities		Other Noncurrent Liabilities		Other Current Assets		Other Current Liabilities
Derivatives designated as hedging instruments:
Interest rate contract	$	18.2	$	—	$	1.0	$	—	$	—
Commodity contracts		1.0		3.8		—		2.1		2.0
Total derivatives designated as hedging instruments	$	19.2	$	3.8	$	1.0	$	2.1	$	2.0
Derivatives not designated as hedging instruments:
Commodity contracts	$	5.4	$	4.6	$	—	$	3.6	$	2.3
Foreign currency exchange contracts		0.8		0.2		—		0.7		0.2
Total derivatives not designated as hedging instruments	$	6.2	$	4.8	$	—	$	4.3	$	2.5
Total derivative instruments	$	25.4	$	8.6	$	1.0	$	6.4	$	4.5

Commodity contracts gains and losses recognized on derivatives designated as cash flow hedges

	Three Months Ended October 31,				Six Months Ended October 31,
	2013		2012		2013		2012
Losses recognized in other comprehensive (loss) income (effective portion)	$	(4.6)	$	(13.1)	$	(10.6)	$	(15.3)
Losses reclassified from accumulated other comprehensive loss to cost of products sold (effective portion)		(3.9)		(12.5)		(12.7)		(19.0)
Change in accumulated other comprehensive loss	$	(0.7)	$	(0.6)	$	2.1	$	3.7
Gains (losses) recognized in cost of products sold (ineffective portion)	$	0.1	$	(0.1)	$	0.1	$	(0.2)

Net realized and unrealized gains and losses recognized in cost of products sold on derivatives not designated as qualified hedging instruments

	Three Months Ended October 31,				Six Months Ended October 31,
	2013		2012		2013		2012
Unrealized (losses) gains on commodity contracts	$	(1.5)	$	(11.2)	$	3.0	$	8.4
Unrealized gains on foreign currency exchange contracts		—		0.9		0.1		1.0
Total unrealized (losses) gains recognized in cost of products sold	$	(1.5)	$	(10.3)	$	3.1	$	9.4
Realized gains (losses) on commodity contracts	$	0.3	$	7.2	$	(6.1)	$	(0.6)
Realized gains (losses) on foreign currency exchange contracts		0.8		(0.3)		1.8		(0.2)
Total realized gains (losses) recognized in cost of products sold	$	1.1	$	6.9	$	(4.3)	$	(0.8)
Total (losses) gains recognized in cost of products sold	$	(0.4)	$	(3.4)	$	(1.2)	$	8.6

Outstanding derivative contracts

	October 31, 2013		April 30, 2013
Commodity contracts	$	324.5	$	347.6
Foreign currency exchange contracts		63.0		56.8
Interest rate contract		750.0		—