FAIR VALUE MEASUREMENTS (Details 2) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	Apr. 30, 2016	Oct. 31, 2015
Assets:
Assets measured at fair value	$ 1,136,413	$ 922,368
Liabilities:
Total liabilities measured at fair value	5,976	6,034
Cash equivalents
Assets:
Assets measured at fair value	814,828	692,067
Short-term investments
Assets:
Assets measured at fair value	195,179	135,107
Prepaid expenses and other
Assets:
Assets measured at fair value	1,173	89
Long-term investments
Assets:
Assets measured at fair value	125,233	95,105
Accrued liabilities
Liabilities:
Total liabilities measured at fair value	548	512
Other long-term obligations
Liabilities:
Other long-term obligations	5,428	5,522
Level 1
Assets:
Assets measured at fair value	749,856	642,073
Liabilities:
Total liabilities measured at fair value	0	0
Level 1 | Cash equivalents
Assets:
Assets measured at fair value	749,856	642,073
Level 2
Assets:
Assets measured at fair value	386,557	280,295
Liabilities:
Total liabilities measured at fair value	5,976	6,034
Level 2 | Cash equivalents
Assets:
Assets measured at fair value	64,972	49,994
Level 2 | Short-term investments
Assets:
Assets measured at fair value	195,179	135,107
Level 2 | Prepaid expenses and other
Assets:
Assets measured at fair value	1,173	89
Level 2 | Long-term investments
Assets:
Assets measured at fair value	125,233	95,105
Level 2 | Accrued liabilities
Liabilities:
Total liabilities measured at fair value	548	512
Level 2 | Other long-term obligations
Liabilities:
Other long-term obligations	5,428	5,522
Level 3
Assets:
Assets measured at fair value	0	0
Liabilities:
Total liabilities measured at fair value	$ 0	$ 0