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Accounts Receivable	3 Months Ended
Accounts Receivable	Apr. 30, 2011
Accounts Receivable [Abstract]
ACCOUNTS RECEIVABLE	(7) ACCOUNTS RECEIVABLE As of October 31, 2010 and April 30, 2011, no customers accounted for greater than 10% of net trade accounts receivable. Allowance for doubtful accounts was $0.1 million and $0.7 million as of October 31, 2010 and April 30, 2011, respectively. Ciena has not historically experienced a significant amount of bad debt expense.