FAIR VALUE MEASUREMENTS (Tables)

6 Months Ended

Jun. 30, 2017

Fair Value Disclosures [Abstract]

Assets Measured and Carried at Fair Value

The tables below present information about the Company’s financial assets that are measured and carried at fair value and indicate the level within the fair value hierarchy of valuation techniques it utilizes to determine such fair value: 

	Fair Value Measurement as of June 30, 2017
	Total		Level 1		Level 2		Level 3
	(in thousands)
Money market funds	$	40,261	$	40,261	$	—	$	—
Commercial paper		58,428		—		58,428		—
Government and government agency bonds		79,254		—		79,254		—
Corporate bonds		19,302		—		19,302		—
Certificates of deposit		648		648		—		—
Total assets	$	197,893	$	40,909	$	156,984	$	—

	Fair Value Measurement as of December 31, 2016
	Total		Level 1		Level 2		Level 3
	(in thousands)
Money market funds	$	1,147	$	1,147	$	—	$	—
Commercial paper		69,304		—		69,304		—
Government and government agency bonds		105,287		—		105,287		—
Corporate bonds		20,834		—		20,834		—
Certificates of deposit		11,343		11,343		—		—
Total assets	$	207,915	$	12,490	$	195,425	$	—