The percentage of voting rights of common stock. Includes eligibility to vote and votes per share owned.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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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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- Definition

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

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Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities.

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Amount of noncash expense for share-based payment arrangement.

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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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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- Definition

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

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

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

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

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No definition available.

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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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- 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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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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No definition available.

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- Definition

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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- Definition

Purchase price of common stock expressed as a percentage of its fair value.

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No definition available.

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Stock-Based Compensation - Additional information (Details) - USD ($)	1 Months Ended		12 Months Ended
	Dec. 31, 2018	May 31, 2014	Dec. 31, 2019	Dec. 31, 2018
Stock-Based Compensation
Reserved for issuance (in shares)		233,722
Voting rights of all classes of stock (in percent)		10.00%
Exercise price for incentive stock options to the percentage of fair market value		110.00%
Annual increase in the number of shares to the shares of common stock		77,908	763,973
Stock option granted			696,874
Weighted-average exercise price of stock option granted			$ 8.52
Options outstanding (in dollars)			$ 258,000
Stock-based compensation expense			1,928,000	$ 1,526,000
Stock-based compensation expense			$ 2,010,000	1,658,000
Assets	$ 455,000			455,000
Liabilities	455,000			$ 455,000
Employee
Stock-Based Compensation
Stock option granted			550,582	351,516
Weighted-average exercise price of stock option granted			$ 5.97	$ 9.89
Total unrecognized compensation costs			$ 4,300,000
Unrecognized stock-based compensation expenses expected to be recognized			2 years 7 months 21 days
Aggregate intrinsic value			$ 51,000	$ 3,000
Stock-based compensation expense			$ 1,900,000	$ 1,500,000
Non employee
Stock-Based Compensation
Stock option granted			69,875	16,000
Weighted-average exercise price of stock option granted			$ 5.47	$ 12.37
Total unrecognized compensation costs			$ 289,000
Unrecognized stock-based compensation expenses expected to be recognized			3 years 2 months 16 days
Stock-based compensation expense			$ 77,000	$ 38,000
Stock option liability
Stock-Based Compensation
Liabilities	455,000			455,000
Deferred charge related to stock options
Stock-Based Compensation
Assets	$ 455,000			455,000
Options
Stock-Based Compensation
Annual increase in the number of shares to the percentage of the issued and outstanding common stock		20.00%
Vesting period (in years)		4 years
Expiration period (in years)		10 years
Options \| Number of shares excess granted under the 2014 Plan
Stock-Based Compensation
Stock option granted	76,417
Options \| Stock option liability \| Accrued liabilities \| Number of shares excess granted under the 2014 Plan
Stock-Based Compensation
Liabilities	$ 455,000			455,000
Options \| Deferred charge related to stock options \| Prepaid expenses and other current assets \| Number of shares excess granted under the 2014 Plan
Stock-Based Compensation
Assets	$ 455,000			$ 455,000