Segment and Entity Wide Disclosures (Details) (USD $) In Thousands	3 Months Ended		9 Months Ended
	Jul. 31, 2011	Jul. 31, 2010	Jul. 31, 2011	Jul. 31, 2010
Revenue:
Revenue	$ 435,313	$ 389,675	$ 1,286,515	$ 819,022
Segment profit (loss):
Segment profit (loss)	91,681	43,140	230,606	107,067
Selling and marketing	(61,895)	(52,127)	(180,755)	(131,692)
General and administrative	(28,172)	(32,649)	(98,966)	(66,915)
Acquisition and integration costs	(4,822)	(17,033)	(39,748)	(83,285)
Amortization of intangible assets	(13,673)	(38,727)	(56,131)	(61,829)
Restructuring costs	(504)	(2,157)	(5,190)	(3,985)
Change in fair value of contingent consideration			(3,289)
Interest and other financial charges net	(12,630)	(8,658)	(21,092)	(11,624)
(Provision) benefit for income taxes	(1,435)	(1,644)	(5,205)	(934)
Consolidated net loss	(31,450)	(109,855)	(173,192)	(253,197)
Packet-Optical Transport [Member]
Revenue:
Revenue	266,551	242,057	825,667	423,216
Segment profit (loss):
Segment profit (loss)	51,827	12,874	127,359	26,402
Packet-Optical Switching [Member]
Revenue:
Revenue	40,682	34,806	107,223	90,638
Segment profit (loss):
Segment profit (loss)	12,783	10,320	34,147	13,749
Carrier Ethernet Service Delivery [Member]
Revenue:
Revenue	40,475	33,802	99,034	149,047
Segment profit (loss):
Segment profit (loss)	6,519	(3,212)	12,409	31,642
Software and Services [Member]
Revenue:
Revenue	87,605	79,010	254,591	156,121
Segment profit (loss):
Segment profit (loss)	$ 20,552	$ 23,158	$ 56,691	$ 35,274