Short-term and Long-term Investments (Tables)

9 Months Ended

Jul. 31, 2014

Investments, Debt and Equity Securities [Abstract]

Short-term and long-term investments

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

	July 31, 2014
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
U.S. government obligations:
Included in short-term investments	$	90,210	$	42	—			$	90,252
Included in long-term investments	65,043		—		(24		)	65,019
	$	155,253	$	42	$	(24	)	$	155,271
Commercial paper:
Included in short-term investments	29,998		—		—			29,998
	$	29,998	$	—	$	—		$	29,998

	October 31, 2013
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
U.S. government obligations:
Included in short-term investments	$	99,974	$	11	$	—	$	99,985
Included in long-term investments	14,996		35		—		15,031
	$	114,970	$	46	$	—	$	115,016
Commercial paper:
Included in short-term investments	24,994		—		—		24,994
	$	24,994	$	—	$	—	$	24,994

Legal maturities of debt investments

The following table summarizes final legal maturities of debt investments at July 31, 2014 (in thousands):

	Amortized Cost		Estimated Fair Value
Less than one year	$	120,208	$	120,250
Due in 1-2 years	65,043		65,019
	$	185,251	$	185,269