SHORT-TERM AND LONG-TERM INVESTMENTS (Details) - USD ($) $ in Thousands	Jan. 31, 2016	Oct. 31, 2015
Long Term Investments
Amortized Cost	$ 335,104
Estimated Fair Value	335,070
U.S. government obligations
Long Term Investments
Amortized Cost	305,128	$ 205,279
Gross Unrealized Gains	147	10
Gross Unrealized Losses	(181)	(66)
Estimated Fair Value	305,094	205,223
U.S. government obligations \| Short-term investments
Long Term Investments
Amortized Cost	180,087	110,108
Gross Unrealized Gains	30	10
Gross Unrealized Losses	(83)	0
Estimated Fair Value	180,034	110,118
U.S. government obligations \| Other Long-term investments
Long Term Investments
Amortized Cost	125,041	95,171
Gross Unrealized Gains	117	0
Gross Unrealized Losses	(98)	(66)
Estimated Fair Value	125,060	95,105
Commercial paper
Long Term Investments
Amortized Cost	29,976	24,989
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	29,976	24,989
Commercial paper \| Short-term investments
Long Term Investments
Amortized Cost	29,976	24,989
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	$ 29,976	$ 24,989

This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.2)
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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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