Segment and Entity Wide Disclosures (Details 1) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Jul. 31, 2012	Jul. 31, 2011	Jul. 31, 2012	Jul. 31, 2011	Oct. 31, 2011
Ciena's geographic distribution of revenue
Revenue	$ 474,090	$ 435,313	$ 1,368,392	$ 1,286,515
Ciena's geographic distribution of equipment, furniture and fixtures
Equipment, furniture and fixtures, net	118,568		118,568		122,558
United States [Member]
Ciena's geographic distribution of revenue
Revenue	237,288	227,524	723,034	678,674
Ciena's geographic distribution of equipment, furniture and fixtures
Equipment, furniture and fixtures, net	60,331		60,331		60,848
Canada[Member]
Ciena's geographic distribution of revenue
Revenue	49,042	43,815	137,129	128,770
Ciena's geographic distribution of equipment, furniture and fixtures
Equipment, furniture and fixtures, net	47,647		47,647		47,424
Other International [Member]
Ciena's geographic distribution of revenue
Revenue	187,760	163,974	508,229	479,071
Ciena's geographic distribution of equipment, furniture and fixtures
Equipment, furniture and fixtures, net	$ 10,590		$ 10,590		$ 14,286
Company A [Member] | Maximum [Member]
Ciena's geographic distribution of revenue
Revenue, Net, Percentage	10.00%
Company B [Member] | Maximum [Member]
Ciena's geographic distribution of revenue
Revenue, Net, Percentage	10.00%	10.00%	10.00%