Marketable Securities (Tables)

9 Months Ended

Jul. 31, 2013

Investments, Debt and Equity Securities [Abstract]

Short-term and long-term investments

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

	July 31, 2013
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
U.S. government obligations	$	114,960	43		$	—	$	115,003
Included in short-term investments	$	99,964	$	17	$	—	$	99,981
Included in long-term investments	14,996		26		—		15,022
	$	114,960	$	43	$	—	$	115,003

	October 31, 2012
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
U.S. government obligations	$	49,987	$	70	$	—	$	50,057
Included in short-term investments	$	49,987	$	70	$	—	$	50,057
Included in long-term investments	—		—		—		—
	$	49,987	$	70	$	—	$	50,057

Legal maturities of debt investments

The following table summarizes final legal maturities of debt investments at July 31, 2013 (in thousands):

	Amortized Cost		Estimated Fair Value
Less than one year	$	99,964	$	99,981
Due in 1-2 years	14,996		15,022
	$	114,960	$	115,003