Short-Term and Long-Term Investments (Tables)
 12 Months Ended
Oct. 31, 2012
Investments, Debt and Equity Securities [Abstract]  
Short-term and Long-term investments
As of October 31, 2011, long-term investments are comprised of the following (in thousands):

 
October 31, 2011
 
Amortized Cost
 
Gross Unrealized
Gains
 
Gross Unrealized
Losses
 
Estimated Fair
Value
US government obligations
$
49,933

 
$
331

 
$
—

 
$
50,264

 
$
49,933

 
$
331

 
$
—

 
$
50,264


As of October 31, 2012, short-term investments have final legal maturities of less than one year and are comprised of the following (in thousands):

 
October 31, 2012
 
Amortized Cost
 
Gross Unrealized
Gains
 
Gross Unrealized
Losses
 
Estimated Fair
Value
US government obligations
$
49,987

 
$
70

 
$
—

 
$
50,057

 
$
49,987

 
$
70

 
$
—

 
$
50,057