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Stock-based Compensation - Stock Option Activity (Details)	9 Months Ended
	Sep. 30, 2020 USD ($) $ / shares shares
Options [Roll Forward]
Balance as of December 31, 2019 (in share) | shares	1,865
Common stock shares to be issued (in shares) | shares	530,000
Cancelled/forfeited (in share) | shares	(529)
Balance as of September 30, 2020 (in share) | shares	531,336
Vested as of September 30, 2020 | shares	39,114
Vested and expected to be vested as of September 30, 2020 | shares	482,121
Weighted Average Exercise Price [Roll Forward]
Balance as of December 31, 2019 (in dollars per share) | $ / shares	$ 2,968.22
Granted (in dollars per share) | $ / shares	2.12
Cancelled/forfeited (in dollars per share) | $ / shares	2,486.82
Balance as of September 30, 2020 (in dollars per share) | $ / shares	10.01
Vested as of September 30, 2020 | $ / shares	106.86
Vested and expected to be vested as of September 30, 2020 | $ / shares	$ 10.66
Aggregate Intrinsic Value [Roll Forward]
Balance as of September 30, 2020 | $	$ 233,000
Vested as of September 30, 2020 | $	17,500
Vested and expected to be vested as of September 30, 2020 | $	$ 211,500

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Share based compensation arrangement by share based payment award options aggregate intrinsic value roll forward1.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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