Collaborations (Tables)

9 Months Ended

Sep. 30, 2020

Organization Consolidation And Presentation Of Financial Statements [Abstract]

Change in Accounts Receivable, Contract Asset and Liabilities

The following table presents the changes in accounts receivable, contract assets and liabilities for the nine months ended September 30, 2020 (in thousands)

	Balance at December 31, 2019		Additions		Deductions			Balance at September 30, 2020
Accounts receivable and contract assets:
Billed receivables - Sanofi	$	—	$	150,000	$	(150,000	)	$	—
Unbilled receivables - Sanofi		—		577		—			577
Total accounts receivable and contract assets	$	—	$	150,577	$	(150,000	)	$	577
Contract Liabilities:
Deferred Revenue - Vertex	$	52,991	$	—	$	(10,373	)	$	42,618
Deferred Revenue - Sanofi		—		150,577		(10,876	)		139,701
Total contract liabilities	$	52,991	$	150,577	$	(21,249	)	$	182,319