Changes in Restructuring Liability (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
	Jan. 31, 2013	Jan. 31, 2013
Restructuring Cost and Reserve [Line Items]
Liability as of Beginning of period	$ 16,501	$ 2,770
Charge to expense	4,441	20,944
Reductions/recoveries		(1,008)	[1]
Non-cash items	(411)	(207)
Reductions for cash payments, net of refund	(6,094)	(8,018)
Exchange rate fluctuations	169	125
Liability as of End of period	14,606	14,606
Severance
Restructuring Cost and Reserve [Line Items]
Liability as of Beginning of period	9,238	38
Charge to expense	4,441	15,765
Reductions/recoveries		(38)	[1]
Non-cash items	(228)	(328)
Reductions for cash payments, net of refund	(4,985)	(6,991)
Exchange rate fluctuations	138	158
Liability as of End of period	8,604	8,604
Facilities
Restructuring Cost and Reserve [Line Items]
Liability as of Beginning of period	7,263	2,732
Charge to expense		5,179
Reductions/recoveries		(970)	[1]
Non-cash items	(183)	121
Reductions for cash payments, net of refund	(1,109)	(1,027)
Exchange rate fluctuations	31	(33)
Liability as of End of period	$ 6,002	$ 6,002

[1] During the nine months ended January 31, 2013, the Company recovered $1.0 million from a legal settlement (related to premises) attributable to a previous restructuring action.