Fair Value Measurements. Cash Equivalents and Marketable Securities (Tables)

12 Months Ended

Dec. 31, 2019

Fair Value Measurements, Recurring and Nonrecurring

The Company’s financial assets and liabilities subject to fair value measurements on a recurring basis and the level of inputs used in such measurements were as follows:



	December 31, 2019
	Fair Value		Level 1		Level 2		Level 3

	(in thousands)
Financial Assets:
Money market funds	$	10,734	$	10,734	$	—	$	—
Total cash equivalents	$	10,734	$	10,734	$	—	$	—

Corporate bonds	$	16,690	—		$	16,690	—
U.S. government debt securities	362,884		—		362,884		—
Total short-term marketable securities	$	379,574	$	—	$	379,574	$	—

U.S. government debt securities	$	268,783	—		$	268,783	—
Total long-term marketable securities	268,783		—		268,783		—
Total	$	659,091	$	10,734	$	648,357	$	—

Financial Liabilities:
Contingent consideration	$	1,365	—		—		$	1,365
	$	1,365	$	—	$	—	$	1,365



	December 31, 2018
	Fair Value		Level 1		Level 2		Level 3

	(in thousands)
Financial Assets:
Money market funds	$	25,796	$	25,796	$	—	$	—
Total cash equivalents	$	25,796	$	25,796	$	—	$	—

Corporate bonds	$	38,397	$	—	$	38,397	$	—
U.S. government debt securities	235,016		—		235,016		—
U.S. government agency bonds	5,004				5,004
Total short-term marketable securities	$	278,417	$	—	$	278,417	$	—

Corporate bonds	$	3,805	$	—	$	3,805	$	—
U.S. government debt securities	73,758		—		73,758		—
Total long-term marketable securities	$	77,563	$	—	$	77,563	$	—
Total	$	381,776	$	25,796	$	355,980	$	—

Debt Securities, Available-for-sale

The following tables summarizes the Company’s cash equivalents and marketable securities’ amortized costs, gross unrealized gains, gross unrealized losses and estimated fair values by significant investment category:



	December 31, 2019
	Amortized Cost		Gross Unrealized Gain		Gross Unrealized Loss			Estimated Fair Value

	(in thousands)
Money market fund	$	10,734	$	—	$	—		$	10,734
Corporate bond	16,679		11		—			16,690
U.S. government debt securities	630,283		1,422		(39		)	631,666
Total	$	657,696	$	1,433	$	(39	)	$	659,090



	December 31, 2018
	Amortized Cost		Gross Unrealized Gain		Gross Unrealized Loss			Estimated Fair Value

	(in thousands)
Money market fund	$	25,796	$	—	$	—		$	25,796
Corporate bond	42,273		—		(71		)	42,202
U.S. government debt securities	308,775		235		(236		)	308,774
U.S. government agency bonds................	5,014		—		(10		)	5,004
Total	$	381,858	$	235	$	(317	)	$	381,776