Income Taxes - Schedule of Significant Components of Deferred Tax Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Net operating loss carryforwards	$ 24,869	$ 20,066	$ 13,093
Capitalized research and development expenses	14,181	7,855	6,684
Research credits and other state credits	3,565	1,368	1,171
Intangible assets	4,176	4,926	28
Depreciation and amortization	(120)	(260)	(360)
Reserve and accruals	1,648	891	677
Valuation allowance	$ (48,319)	$ (34,846)	$ (21,293)

Deferred tax assets, depreciation and amortization.

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Deferred tax assets, tax credit carryforwards, research and other state.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from intangible assets including goodwill.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from in-process research and development costs expensed in connection with a business combination.

+ References

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-Publisher FASB
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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from reserves and accruals.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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