Closing price of common stock.

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- Definition

Employee Service Share Based Compensation Unrecognized Compensation Costs Weighted Average Period Of Recognition

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- Definition

Aggregate number of common shares reserved for future issuance.

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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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- Definition

Amount of cost to be recognized for option under share-based payment arrangement.

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Number of shares authorized for issuance under share-based payment arrangement.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

Maximum number of shares that may be issued in accordance with the plan as a proportion of outstanding capital stock.

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No definition available.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for fully vested and expected to vest exercisable or convertible options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. 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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Weighted average remaining contractual term of outstanding stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Stock-Based Compensation - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended		9 Months Ended
	Sep. 10, 2019	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 29, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock reserved for issuance (in shares)		4,351,000		4,351,000
Weighted average exercise price, granted (in dollars per share)		$ 0	$ 0	$ 1.53	$ 54.00
Averages contractual term				10 years
Expected dividend yield (as a percent)				0.00%	0.00%
Unrecognized compensation cost, options		$ 0.8		$ 0.8
Operating expenses weighted average period				2 years 1 month 13 days
Closing price of the Company's common stock (in dollars per share)		$ 2.65		$ 2.65
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average exercise price, granted (in dollars per share)				$ 1.89
Unrecognized compensation cost		$ 0.3		$ 0.3
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average vesting term				6 years
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average vesting term				4 years
2017 Equity Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock reserved for issuance (in shares)		2,684		2,684
2017 Equity Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock authorized for issuance (in shares)						24,204
2019 Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock authorized for issuance (in shares)	454,005
Shares of common stock reserved for issuance (in shares)		100,689		100,689
Options expire from date of grant	4 years
Increase in number of shares available for future issuance under stock based awards (as a percent)	5.00%