Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2019

Accounting Policies [Abstract]

Schedule of Restricted Cash

Restricted Cash—

(in thousands)	As of December 31, 2019		As of December 31, 2018
Letter of credit security: Cambridge lease	$	264	$	264
Letter of credit security: Waltham lease	250		—
Letter of credit security: Vienna Austria lease	94		—
Letter of credit security: Allston lease	1,144		—
Corporate credit card collateral	150		100
Total restricted cash (non-current)	$	1,902	$	364

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

The following table provides a reconciliation of cash, cash equivalents, and restricted cash reported within the consolidated balance sheets to the sum to the total of amounts shown in the Company’s consolidated statement of cash flows as of December 31, 2019, 2018 and 2017:

(in thousands)	December 31, 2019		December 31, 2018		December 31, 2017		December 31, 2016
Cash and cash equivalents	$	126,184	$	8,134	$	26,684	$	15,160
Restricted cash, non-current (included within other assets)	1,902		364		364		155
Total cash, cash equivalents and restricted cash	$	128,086	$	8,498	$	27,048	$	15,315

Property and Equipment Useful Life

Property and equipment are stated at cost less accumulated depreciation and amortization. Depreciation and amortization expense is recognized using the straight-line method over the estimated useful life of each asset, as follows:

	Estimated Useful Life
Office furniture	3 years
Computer equipment	3 years
Laboratory equipment	3 to 10 years
Leasehold improvements	Shorter of lease term or 10 years