FAIR VALUE MEASUREMENTS (Details 2) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	Jan. 31, 2016	Oct. 31, 2015
Assets:
Assets measured at fair value	$ 889,432	$ 922,368
Liabilities:
Total liabilities measured at fair value	9,458	6,034
Cash equivalents
Assets:
Assets measured at fair value	554,347	692,067
Short-term investments
Assets:
Assets measured at fair value	210,010	135,107
Prepaid expenses and other
Assets:
Assets measured at fair value	15	89
Long-term investments
Assets:
Assets measured at fair value	125,060	95,105
Accrued liabilities
Liabilities:
Total liabilities measured at fair value	3,607	512
Other long-term obligations
Liabilities:
Other long-term obligations	5,851	5,522
Level 1
Assets:
Assets measured at fair value	509,365	642,073
Liabilities:
Total liabilities measured at fair value	0	0
Level 1 | Cash equivalents
Assets:
Assets measured at fair value	509,365	642,073
Level 2
Assets:
Assets measured at fair value	380,067	280,295
Liabilities:
Total liabilities measured at fair value	9,458	6,034
Level 2 | Cash equivalents
Assets:
Assets measured at fair value	44,982	49,994
Level 2 | Short-term investments
Assets:
Assets measured at fair value	210,010	135,107
Level 2 | Prepaid expenses and other
Assets:
Assets measured at fair value	15	89
Level 2 | Long-term investments
Assets:
Assets measured at fair value	125,060	95,105
Level 2 | Accrued liabilities
Liabilities:
Total liabilities measured at fair value	3,607	512
Level 2 | Other long-term obligations
Liabilities:
Other long-term obligations	5,851	5,522
Level 3
Assets:
Assets measured at fair value	0	0
Liabilities:
Total liabilities measured at fair value	$ 0	$ 0