Summary of significant accounting policies (Tables)

12 Months Ended

Dec. 31, 2017

Summary of Significant Accounting Policies

Schedule of cash, cash equivalents, and restricted cash

The following table presents cash, cash equivalents, and restricted cash as reported on the consolidated balance sheets that equal the total amounts on the consolidated statements of cash flows (in thousands):

	Year Ended
	As of December 31,
	2017		2016		2015
Cash and cash equivalents	$	146,630	$	185,323	$	143,180
Restricted cash included in "Prepaid expenses and other current assets"		—		—		320
Restricted cash included in "Restricted cash and other non-current assets"		1,619		1,619		—
Total	$	148,249	$	186,942	$	143,500

Schedule of estimated useful lives of property, plant and equipment

Asset:	Estimated Useful life
Lab equipment	5 years
Computer equipment and software	3 years
Furniture and equipment	5 years
Leasehold improvements	Shorter of useful life or remaining lease term
Building	30 years