Marketable Securities

3 Months Ended

Apr. 30, 2011

Marketable Securities [Abstract]

MARKETABLE SECURITIES

(5) MARKETABLE SECURITIES

     As of the date indicated, long-term investments are comprised of the following (in thousands):

	April 30, 2011
			Gross Unrealized		Gross Unrealized		Estimated Fair
	Amortized Cost		Gains		Losses		Value
U.S. government obligations	$	49,906	$	192	$	—	$	50,098
	$	49,906	$	192	$	—	$	50,098
Included in long-term investments		49,906		192		—		50,098
	$	49,906	$	192	$	—	$	50,098

     The following table summarizes final legal maturities of debt investments at April 30, 2011 (in thousands):

	Amortized		Estimated
	Cost		Fair Value
Less than one year	$	—	$	—
Due in 1-2 years		49,906		50,098
	$	49,906	$	50,098

     At October 31, 2010, Ciena did not have any investments in marketable debt securities.