Income Taxes (Tables)

12 Months Ended

Dec. 31, 2017

Income Tax Disclosure [Abstract]

Summary of Net Loss Before Provision (Benefit) for Income Taxes

Net loss before provision (benefit) for income taxes consisted of the following (in thousands):

	Year ended December 31,
	2017			2016			2015
United States	$	(27,820	)	$	(27,908	)	$	(28,870	)
International		1,937			(1,165	)		(4,492	)
Total net loss before provision (benefit) for income taxes	$	(25,883	)	$	(29,073	)	$	(33,362	)

Summary of Provision (Benefit) for Income Taxes

The provision (benefit) for income taxes consisted of the following (in thousands):

	Year ended December 31,
	2017			2016			2015
Current
Federal	$	—		$	—		$	—
State		49			63			71
Foreign		256			209			85
Total current		305			272			156
Deferred
Federal	$	—		$	—		$	(1,312	)
State		—			—			(99	)
Foreign		(47	)		(36	)		(8	)
Total deferred		(47	)		(36	)		(1,419	)
Total income tax provision (benefit)	$	258		$	236		$	(1,263	)

Summary of Variation of Effective Provision (Benefit) for Income Taxes from Statutory Federal Income Tax Rate

The provision (benefit) for income tax differed from the amounts computed by applying the U.S. federal income tax rate to pretax loss as a result of the following (in thousands):

	Year ended December 31,
	2017			2016			2015
Federal tax benefit at statutory rate	$	(8,800	)	$	(9,885	)	$	(11,343	)
State tax, net of federal provision (benefit)		32			28			(34	)
Research and development credits		(707	)		(745	)		(667	)
Share-based compensation		(18,154	)		960			1,086
Other permanent differences		814			600			325
Change in US federal Tax Rate		40,377			—			—
Foreign tax rate differential		(445	)		(225	)		(80	)
Net operating (gains) losses not recognized		(12,859	)		9,503			10,762
Release of valuation allowance associated with acquisitions		—			—			(1,312	)
Total income tax provision (benefit)	$	258		$	236		$	(1,263	)

Schedule of Deferred Income Tax Assets and Liabilities

The types of temporary differences that give rise to significant portions of the Company’s deferred tax assets and liabilities are as follows (in thousands):

	Year ended December 31,
	2017			2016			2015
Deferred tax assets
Net operating loss and credit carry-forwards	$	73,016		$	59,863		$	54,858
Research and development credits		8,027			6,094			4,712
Sales tax liability		627			1,131			1,337
Share-based compensation		4,955			7,281			6,694
Accrued liabilities		4,881			6,525			6,090
Gross deferred tax assets		91,506			80,894			73,691
Valuation allowance		(89,235	)		(79,319	)		(71,514	)
Total deferred tax assets		2,271			1,575			2,177
Deferred tax liabilities - Acquired intangibles		(344	)		(803	)		(1,164	)
Deferred tax liabilities - Property and equipment		(1,714	)		(606	)		(883	)
Net deferred tax assets	$	213		$	166		$	130

Summary of Reconciliation of Beginning and Ending Amount of Unrecognized Tax Benefits

In general, it is our practice and intention to reinvest the earnings of our non-U.S. subsidiaries in those operations. Undistributed earnings of foreign subsidiaries are immaterial for all periods presented.

The Company has adopted the accounting policy that interest and penalties recognized are classified as part of its income taxes. The following shows the changes in the gross amount of unrecognized tax benefits as of December 31, 2017 (in thousands):

Balance as of December 31, 2014	$	2,615
Gross amount of increases in unrecognized tax benefits for tax positions taken in current year		499
Gross amount of decreases in unrecognized tax benefits for tax positions taken in prior year		(1,217	)
Balance as of December 31, 2015	$	1,897
Gross amount of increases in unrecognized tax benefits for tax positions taken in current year		538
Gross amount of increases in unrecognized tax benefits for tax positions taken in prior year		25
Balance as of December 31, 2016	$	2,460
Gross amount of increases in unrecognized tax benefits for tax positions taken in current year		547
Gross amount of decreases in unrecognized tax benefits for tax positions taken in prior years		(3	)
Balance as of December 31, 2017	$	3,004