Fair Value Measurement (Tables)

6 Months Ended

Jun. 30, 2021

Fair Value Disclosures [Abstract]

Summary of Financial Assets and Liabilities Subject to Fair Value Measurements on Recurring Basis

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

	Fair Value Measured as of June 30, 2021
	Level 1		Level 2		Level 3		Total
Assets included in:
Money market funds(1)	$	302,816	$	—	$	—	$	302,816
Commercial paper(2)		—		250,413		—		250,413
U.S. government securities(2)		—		789,406		—		789,406
Corporate notes and bonds(2)		—		219,805		—		219,805
Total fair value	$	302,816	$	1,259,624	$	—	$	1,562,440
Liabilities included in:
Assumed common stock warrants (Public)	$	29,354	$	—	$	—	$	29,354
Assumed common stock warrants (Private Placement)		—		119,101		—		119,101
Total fair value	$	29,354	$	119,101	$	—	$	148,455
	Fair Value Measured as of December 31, 2020
	Level 1		Level 2		Level 3		Total
Assets included in:
Money market funds(1)	$	12,235	$	—	$	—	$	12,235
U.S. government securities(2)		—		977,326		—		977,326
Total fair value	$	12,235	$	977,326	$	—	$	989,561
Liabilities included in:
Assumed common stock warrants (Public)	$	436,999	$	—	$	—	$	436,999
Assumed common stock warrants (Private Placement)		—		252,700		—		252,700
Total fair value	$	436,999	$	252,700	$	—	$	689,699

(1) Money market funds are included in cash and cash equivalents on the Condensed Consolidated Balance Sheet.

(2) As of June 30, 2021 and December 31, 2020, marketable securities with original maturities of three months or less of $94.5 million and $105.2 million, respectively, are included in cash and cash equivalents on the Condensed Consolidated Balance Sheet. 

Summary of Major Security Type Assets That Measured at Fair Value on Recurring Basis

The fair value as of June 30, 2021 and December 31, 2020, are as follows (amounts in thousands):

	June 30, 2021
	Amortized Cost		Unrealized Gain		Unrealized Loss			Fair Value
Level 1 securities
Money market funds	$	302,816	$	—	$	—		$	302,816
Level 2 securities
Commercial paper		250,413		—		—			250,413
US government securities		789,570		64		(228	)		789,406
Corporate notes and bonds		220,335		20		(550	)		219,805
Total	$	1,563,134	$	84	$	(778	)	$	1,562,440
	December 31, 2020
	Amortized Cost		Unrealized Gain		Unrealized Loss			Fair Value
Level 1 securities
Money market funds	$	12,235	$	—	$	—		$	12,235
Level 2 securities
US government securities		977,357		24		(55	)		977,326
Total	$	989,592	$	24	$	(55	)	$	989,561

Summary of Estimated Amortized Cost and Fair Value of Available-for-Sale Securities by Contractual Maturity

The estimated amortized cost and fair value of available-for-sale securities by contractual maturity as of June 30, 2021 and December 31, 2020, are as follows (amounts in thousands):

	June 30, 2021				December 31, 2020
	Amortized Cost		Fair Value		Amortized Cost		Fair Value
Due within one year	$	1,213,212	$	1,213,213	$	895,867	$	895,830
Due after one year and through five years		349,922		349,227		93,725		93,731
Total	$	1,563,134	$	1,562,440	$	989,592	$	989,561