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

6 Months Ended

Jun. 30, 2020

Fair Value Disclosures [Abstract]

Schedule of 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:

	June 30, 2020
	Fair Value		Level 1		Level 2		Level 3
	(unaudited)
	(in thousands)
Financial Assets:
Money market funds	$	20,237	$	20,237	$	—	$	—
Total cash equivalents	$	20,237	$	20,237	$	—	$	—
U.S. government debt securities	$	773,160	$	—	$	773,160	$	—
Total short-term marketable securities	$	773,160	$	—	$	773,160	$	—
U.S. government debt securities	$	146,118	$	—	$	146,118	$	—
Total long-term marketable securities	$	146,118	$	—	$	146,118	$	—
Total	$	939,515	$	20,237	$	919,278	$	—
Financial Liabilities:
Contingent consideration	$	1,175	$	—	$	—	$	1,175
Total	$	1,175	$	—	$	—	$	1,175

	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
Total	$	1,365	$	—	$	—	$	1,365

Schedule of Level 3 Activity

The following table summarizes the activities for the Level 3 financial instruments for the three and six months ended June 30, 2020 and 2019:

	Redeemable Noncontrolling Interest								Contingent Consideration
	Three Months Ended June 30,				Six Months Ended June 30,				Three Months Ended June 30,				Six Months Ended June 30,
	2020		2019		2020		2019		2020		2019		2020		2019
	(unaudited)
	(in thousands)
Fair value — beginning of period	$	45,500	$	46,500	$	49,600	$	41,800	$	1,175	$	—	$	1,365	$	—
Initial valuation on the date of acquisition	—		—		—		—		—		1,065		—		1,065
Increase (decrease) in fair value	6,186		922		3,159		5,944		—		—		(190)		—
Net loss for the period	(1,286)		(622)		(2,359)		(944)		—		—		—		—
Fair value — end of period	$	50,400	$	46,800	$	50,400	$	46,800	$	1,175	$	1,065	$	1,175	$	1,065

Schedule of 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:

	June 30, 2020
	Amortized Cost		Gross Unrealized Gain		Gross Unrealized Loss		Estimated Fair Value
	(unaudited)
	(in thousands)
Money market fund	$	20,237	$	—	$	—	$	20,237
U.S. government debt securities	913,655		5,623		—		919,278
Total	$	933,892	$	5,623	$	—	$	939,515

	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		1,423		(39)		631,667
Total	$	657,696	$	1,434	$	(39)	$	659,091