Income Taxes (Tables)

12 Months Ended

Dec. 31, 2015

Income Tax Disclosure [Abstract]

Schedule of Income (Loss) Before Income Taxes Attributed to Geographic Locations

	December 31,
	2015			2014			2013
United States	$	(17,671	)	$	(49,850	)	$	(18,497	)
Foreign		(64,506	)		(7,663	)		—
Income (loss) before income taxes	$	(82,177	)	$	(57,513	)	$	(18,497	)

Summary of Statutory Federal Tax Rate to Income or Loss before Taxes

Income tax expense in 2015, 2014, and 2013 differed from the amount expected by applying the statutory federal tax rate to the income or loss before taxes as summarized below:

	December 31,
	2015			2014			2013
Federal tax benefit at statutory rate		34	%		34	%		34	%
State tax benefit net of federal effect		—			—			—
Change in valuation allowance		(8	)%		(23	)%		(42	)%
Research and development credits		2	%		2	%		9	%
Non-deductible warrant		—			(7	)%		—
Foreign loss not benefitted		(27	)%		(5	)%		—
Non-deductible expenses and other		(2	)%		(1	)%		(1	)%
Total		0	%		0	%		0	%

Significant Components of Net Deferred Tax Assets

Significant components of the Company’s net deferred tax assets at December 31, 2015 and 2014 are as follows (in thousands):

	December 31,
	2015			2014
Net operating loss carry forwards	$	33,684		$	32,143
Research and development tax credits		4,982			2,776
Accruals and reserves		4,465			1,693
Depreciation and amortization		42			33
Total deferred tax assets		43,173			36,645
Less: Valuation allowance		(43,173	)		(36,645	)
Net deferred tax assets	$	—		$	—

Reconciliation of Amount of Unrecognized Tax Benefits

A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows (in thousands):

	Amount
Balance at January 1, 2013	$	73
Increases of unrecognized tax benefits taken in prior years		31
Increases of unrecognized tax benefits related to current year		183
Balance at December 31, 2013	$	287
Decreases based on tax positions taken during a prior period		(102	)
Increases based on tax positions taken during a current period		147
Balance at December 31, 2014	$	332
Increases based on tax positions taken during a prior period		3,562
Increases based on tax positions taken during a current period		167
Balance at December 31, 2015	$	4,061