SHORT-TERM AND LONG-TERM INVESTMENTS (Tables)

9 Months Ended

Jul. 31, 2017

Investments, Debt and Equity Securities [Abstract]

Short-term and long-term investments

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

	July 31, 2017
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
U.S. government obligations:
Included in short-term investments	$	225,032	$	—	(272		)	$	224,760
Included in long-term investments	59,976		—		(102		)	59,874
	$	285,008	$	—	$	(374	)	$	284,634
Commercial paper:
Included in short-term investments	$	9,983	—		—			$	9,983
	$	9,983	$	—	$	—		$	9,983

	October 31, 2016
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
U.S. government obligations:
Included in short-term investments	$	260,125	$	140	$	(6	)	$	260,259
Included in long-term investments	90,145		57		(30		)	90,172
	$	350,270	$	197	$	(36	)	$	350,431
Commercial paper:
Included in short-term investments	$	14,989	—		—			$	14,989
	$	14,989	$	—	$	—		$	14,989

Legal maturities of debt investments

The following table summarizes the final legal maturities of debt investments at July 31, 2017 (in thousands):

	Amortized Cost		Estimated Fair Value
Less than one year	$	235,015	$	234,743
Due in 1-2 years	59,976		59,874
	$	294,991	$	294,617