Balance Sheet Components (Tables)

12 Months Ended

Dec. 31, 2016

Organization Consolidation And Presentation Of Financial Statements [Abstract]

Cash and cash equivalents consisted of the following (in thousands):

	December 31,
	2016		2015
Cash	$	79,239	$	75,685
Money market funds		94,543		77,639
Total cash and cash equivalents	$	173,782	$	153,324

Schedule of Property and Equipment

Property and equipment consisted of the following (in thousands):

	December 31,
	2016			2015
Laboratory equipment	$	18,533		$	18,233
Computer equipment		5,678			5,701
Furniture and fixtures		5,533			5,361
Leasehold improvements		93,564			93,380
Building shell (Refer to Note 8)		53,879			53,879
Construction in progress		109			193
Total property and equipment	$	177,296		$	176,747
Less: accumulated depreciation		(53,639	)		(47,727	)
Property and equipment, net	$	123,657		$	129,020

Summary of Amortized Cost, Gross Unrealized Holding Gains or Losses, and Fair Value of Available-for-Sale Investments

All investments are classified as available-for-sale. The amortized cost, gross unrealized holding gains or losses, and fair value of the Company’s available-for-sale investments by major investments type are summarized in the tables below (in thousands):

	December 31, 2016
	Amortized Cost		Gross Unrealized Holding Gains		Gross Unrealized Holding Losses			Fair Value
Corporate bonds	$	126,550	$	182	$	(49	)	$	126,683
Certificate of deposits		1,037		—		—			1,037
Bond and mutual funds		22,305		157		—			22,462
Equity investments		125		100		—			225
Total investments	$	150,017	$	439	$	(49	)	$	150,407

	December 31, 2015
	Amortized Cost		Gross Unrealized Holding Gains		Gross Unrealized Holding Losses			Fair Value
Corporate bonds	$	126,522	$	54	$	(473	)	$	126,103
Certificate of deposits		8,217		—		(2	)		8,215
Bond and mutual funds		25,052		—		—			25,052
Equity investments		126		71		—			197
Total investments	$	159,917	$	125	$	(475	)	$	159,567

Summary of Contractual Maturities Available-for-Sale Investments at Fair Value

The contractual maturities of available-for-sale investments were as follows (in thousands):

	December 31, 2016
Within one year	$	67,075
After one year through four years		60,645
Total debt investments		127,720
Bond and mutual funds		22,462
Equity investments		225
Total investments		150,407

Schedule of Accrued Liabilities

Accrued liabilities consisted of the following (in thousands):

	December 31,
	2016		2015
Preclinical and clinical trial accruals	$	29,550	$	27,973
Payroll and related accruals		14,232		13,535
Professional services		1,252		1,662
Other		5,880		4,762
Total accrued liabilities	$	50,914	$	47,932