CASH, CASH EQUIVALENTS AND MARKETABLE SECURITIES (Tables)

12 Months Ended

Dec. 31, 2017

Cash And Cash Equivalents [Abstract]

Summary of Company Financial Assets with Maturities of Less Than 90 Days Included in Cash Equivalents

The following table summarizes the Company’s financial assets with maturities of less than 90 days from the date of purchase included in cash equivalents in the consolidated balance sheets for each of the periods indicated:

	As of December 31
	2017		2016
	(in thousands)
Money market funds		352,370		1,147
Corporate bonds		16,720		—
Government and government agency bonds		49,972		—
Total		419,062		1,147

Summary of Company Cash, Cash Equivalents and Investments

. The following tables summarize the Company’s cash, cash equivalents and investments for each of the periods indicated:

	As of December 31, 2017
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Market Value
	(in thousands)
Cash and money market funds	$	532,999	$	—	$	—		$	532,999
Commercial paper - current		133,368		—		—			133,368
Government and government agency bonds - current		294,915		2		(200	)		294,717
Corporate bonds
Current		118,121		—		(145	)		117,976
Non-current		10,016		—		(36	)		9,980
Total assets	$	1,089,419	$	2	$	(381	)	$	1,089,040
As reported:
Cash and cash equivalents	$	599,698	$	2	$	(9	)	$	599,691
Short-term investments		479,705		—		(336	)		479,369
Long-term investments		10,016		—		(36	)		9,980
Total assets	$	1,089,419	$	2	$	(381	)	$	1,089,040
	As of December 31, 2016
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Market Value
	(in thousands)
Cash and money market funds	$	122,420	$	—	$	—		$	122,420
Commercial paper - current		69,355		—		(51	)		69,304
Government and government agency bonds - current		105,340		—		(53	)		105,287
Corporate bonds - current		20,850		—		(16	)		20,834
Total assets	$	317,965	$	—	$	(120	)	$	317,845
As reported:
Cash and cash equivalents	$	122,420	$	—	$	—		$	122,420
Short-term investments		195,545		—		(120	)		195,425
Total assets	$	317,965	$	—	$	(120	)	$	317,845