Deferred Revenue (Tables)

6 Months Ended

Jun. 30, 2019

Revenue Recognition [Abstract]

Schedule of Deferred Revenue Activity

The following is a summary of the Company’s deferred revenue activity as of June 30, 2019:

(in thousands)	BED				Grants			Total
Balance as of December 31, 2018		$	644		$	568		$	1,212
Additions to deferred revenue		—			2,400			2,400
Recognized as revenue		(644		)	(1,594		)	(2,238		)
Balance as of June 30, 2019		$	—		$	1,374		$	1,374