Summary of Significant Accounting Policies (Tables)

3 Months Ended

Mar. 31, 2020

Accounting Policies [Abstract]

Schedule of Restricted Cash

Restricted Cash—

(in thousands)	As of March 31, 2020		As of December 31, 2019
Letter of credit security: Cambridge lease	$	264	$	264
Letter of credit security: Waltham lease	250		250
Letter of credit security: Vienna Austria lease	92		94
Letter of credit security: Allston lease	1,144		1,144
Corporate credit card collateral	150		150
Total restricted cash (non-current)	$	1,900	$	1,902

Schedule of Reconciliation of Cash, Cash Equivalents, and Restricted Cash

The following table provides a reconciliation of cash, cash equivalents, and restricted cash reported within the condensed consolidated balance sheets to the sum of the total of amounts shown in the Company’s condensed consolidated statements of cash flows as of March 31, 2020, December 31, 2019, March 31, 2019 and December 31, 2018: 

(in thousands)	March 31, 2020		December 31, 2019		March 31, 2019		December 31, 2018
Cash and cash equivalents	$	115,054	$	126,184	$	22,299	$	8,134
Restricted cash, non-current	1,900		1,902		947		364
Total cash, cash equivalents and restricted cash	$	116,954	$	128,086	$	23,246	$	8,498