The following tables summarize the Company’s cash, cash equivalents, and investments’ adjusted cost, gross unrealized gains, gross unrealized losses, and fair value by significant investment category recorded as cash and cash equivalents, short-term, or long-term investments as of March 31, 2018 and 2019 (in thousands):



March 31, 2018	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value		Cash & Cash Equivalents		Short-term investments (due in 1 year or less)
Cash	$	308,734	$	—	$	—		$	308,734	$	308,734	$	—
Level 1:
Mutual Funds	13,336		186		(67		)	13,455		—		13,455
US Treasury Notes	129,373		7		(60		)	129,320		30,178		99,142
Money Market Funds	344		—		—			344		344		—
Subtotal	143,053		193		(127		)	143,119		30,522		112,597
Level 2:
Government Agency Securities	46,354		—		(56		)	46,298		6,978		39,320
Municipal Bonds	3,591		—		—			3,591		3,591		—
Commercial Paper	84,512		—		—			84,512		40,836		43,676
Corporate Bonds	54,701		—		(212		)	54,489		—		54,489
Certificates of Deposits ("CDs")	19,231		—		—			19,231		—		19,231
Subtotal	208,389		—		(268		)	208,121		51,405		156,716

Total cash, cash equivalents and investments measured at fair value	$	660,176	$	193	$	(395	)	$	659,974	$	390,661	$	269,313



March 31, 2019	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value		Cash & Cash Equivalents		Short-term investments (due in 1 year or less)
Cash	$	202,509	$	—	$	—		$	202,509	$	202,509	$	—
Level 1:
Mutual Funds	13,420		197		(285		)	13,332		—		13,332
US Treasury Notes	—		—		—			—		—		—
Money Market Funds	—		—		—			—		—
Subtotal	13,420		197		(285		)	13,332		—		13,332

Total cash, cash equivalents and investments measured at fair value	$	215,929	$	197	$	(285	)	$	215,841	$	202,509	$	13,332