MARKETABLE SECURITIES (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Marketable Securities [Line Items]
Amortized Cost	$ 191,616	$ 165,232
Gross Unrealized Gains	82	28
Gross Unrealized Losses	0	0
Fair Value	191,698	165,260
Due In One Year Or Less
Marketable Securities [Line Items]
Amortized Cost	93,548	165,232
Gross Unrealized Gains	26	28
Gross Unrealized Losses	0	0
Fair Value	93,574	$ 165,260
Due After One Year Through Two Years
Marketable Securities [Line Items]
Amortized Cost	98,068
Gross Unrealized Gains	56
Gross Unrealized Losses	0
Fair Value	$ 98,124