Stock-Based Compensation (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Minimum [Member]
Stock-based compensation
Vesting period	3 years
Maximum [Member]
Stock-based compensation
Vesting period	4 years
Board Director [Member]
Stock-based compensation
Vesting period	1 year
Stock Options [Member]
Stock-based compensation
Options granted (in shares)	1,550,270	306,304
Percentage of vesting of awards	25.00%	25.00%
Resulting weighted average grant date fair value	$ 0.58	$ 1.25
Remaining unrecognized compensation cost of non-vested stock options	$ 600
Weighted-average remaining requisite service period of recognition of unrecognized compensation cost	1 year 10 months 10 days
Stock Options [Member] \| Minimum [Member]
Stock-based compensation
Vesting period	1 year
Stock Options [Member] \| Maximum [Member]
Stock-based compensation
Vesting period	4 years
Performance Share Options [Member]
Stock-based compensation
Options granted (in shares)		174,272
Restricted Stock Units (RSUs) [Member]
Stock-based compensation
Compensation cost recognized	$ 0
Restricted Stock Units outstanding	280,000
2018 Equity Incentive Plan (the "2018 Plan")
Stock-based compensation
Number of authorized shares	1,500,000
Number of authorized additional shares to be issued	709,889
Number of shares reserved for issuance	208,789
2018 Equity Incentive Plan (the "2018 Plan") \| Stock Options [Member]
Stock-based compensation
Life of stock option awards granted	10 years

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 option under share-based payment arrangement.

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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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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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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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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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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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

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

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Amount of cost expensed and capitalized for award under share-based payment arrangement.

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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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