Stockholders' Equity - Summary of RSU Activity (Details) - 2013 Equity Incentive Plan - USD ($)		3 Months Ended
Jan. 09, 2014	Mar. 31, 2020
Restricted Stock Units information
Period for unrecognized compensation expense related to unvested options yet has not been recognized		1 year 10 months 24 days
Upon first anniversary of start date
Restricted Stock Units information
Percent of shares subject to option grant that will vest	25.00%
RSU
NUMBER OF SHARES
Unvested at beginning of period		324,550
Forfeited		(7,870)
Unvested at end of period		316,680
WEIGHTED-AVERAGE GRANT DATE FAIR VALUE
Unvested at beginning of period		$ 4.53
Forfeited		4.53
Unvested at end of period		$ 4.53
RSU \| Non-executive employees
Restricted Stock Units information
Unrecognized compensation expense related to unvested service RSUs		$ 1,049,391
Period for unrecognized compensation expense related to unvested options yet has not been recognized		1 year 6 months

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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Percentage of vesting of award under share-based payment arrangement.

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