Segments and Entity Wide Disclosures (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jul. 31, 2015	Jul. 31, 2014	Jul. 31, 2015	Jul. 31, 2014
Revenue:
Revenue	$ 602,932	$ 603,562	$ 1,753,696	$ 1,697,326
Segment profit (loss) and the reconciliation to consolidated net income (loss)
Segment profit	169,490	166,288	466,233	424,841
Less: Non-performance operating expenses
Selling and marketing	81,650	81,919	240,833	243,929
General and administrative	29,743	36,285	89,598	98,264
Acquisition and integration costs	2,435	0	3,455	0
Amortization of intangible assets	11,019	11,019	33,057	34,951
Restructuring costs	192	63	8,260	178
Add: Other non-performance financial items
Interest expense and other income (loss), net	(17,374)	(17,836)	(57,764)	(47,787)
Less: Provision for income taxes	3,452	3,006	7,767	9,666
Net income (loss)	23,625	16,160	25,499	(9,934)
Converged Packet Optical
Revenue:
Revenue	407,970	382,031	1,177,441	1,072,272
Segment profit (loss) and the reconciliation to consolidated net income (loss)
Segment profit	118,223	104,020	322,652	279,299
Packet Networking
Revenue:
Revenue	57,209	69,464	165,480	187,699
Segment profit (loss) and the reconciliation to consolidated net income (loss)
Segment profit	7,628	14,566	18,910	23,147
Optical Transport
Revenue:
Revenue	17,482	31,016	56,275	100,729
Segment profit (loss) and the reconciliation to consolidated net income (loss)
Segment profit	2,813	8,900	13,428	29,259
Software and Services
Revenue:
Revenue	120,271	121,051	354,500	336,626
Segment profit (loss) and the reconciliation to consolidated net income (loss)
Segment profit	$ 40,826	$ 38,802	$ 111,243	$ 93,136