Changes In Restructuring Liability (Detail) - USD ($) $ in Thousands	12 Months Ended
	Apr. 30, 2016	Apr. 30, 2015	Apr. 30, 2014
Restructuring Cost and Reserve [Line Items]
Liability, Beginning period	$ 1,146	$ 2,813
Restructuring charges, net	33,013	9,468	$ 3,682
Reductions for cash payments	(26,459)	(10,582)
Non-cash items	(1,843)
Exchange rate fluctuations	105	(553)
Liability, Ending period	5,962	1,146	2,813
Severance
Restructuring Cost and Reserve [Line Items]
Liability, Beginning period	375
Restructuring charges, net	32,151	9,224	800
Reductions for cash payments	(25,625)	(8,396)
Non-cash items	(1,752)
Exchange rate fluctuations	144	(453)
Liability, Ending period	5,293	375
Facilities
Restructuring Cost and Reserve [Line Items]
Liability, Beginning period	771	2,813
Restructuring charges, net	862	244	2,900
Reductions for cash payments	(834)	(2,186)
Non-cash items	(91)
Exchange rate fluctuations	(39)	(100)
Liability, Ending period	$ 669	$ 771	$ 2,813