Represents the grant date fair value of options granted during the reporting period.

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

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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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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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Number of shares related to Restricted Stock Award forfeited during the period.

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Stock-Based Compensation (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Stock Options [Member]
Stock-based compensation
Options granted (in shares)			36,400
Restricted Stock Units (RSUs) [Member]
Stock-based compensation
Additional restricted stock units issued		3,938	17,088		14,000
Stock units forfeited	850
Vested stock units			0
Compensation cost recognized			$ 0
2018 Equity Incentive Plan (the "2018 Plan") [Member]
Stock-based compensation
Number of authorized shares	775,000		775,000
Number of additional shares authorized			35,494
Number of shares reserved for issuance	676,124		676,124
2018 Equity Incentive Plan (the "2018 Plan") [Member] \| Minimum [Member]
Stock-based compensation
Stock awards vesting period			1 year
2018 Equity Incentive Plan (the "2018 Plan") [Member] \| Maximum [Member]
Stock-based compensation
Stock awards vesting period			4 years
2018 Equity Incentive Plan (the "2018 Plan") [Member] \| Stock Options [Member]
Stock-based compensation
Life of stock option awards granted			10 years
Options granted, grant date fair value			$ 3.95
Options granted (in shares)			36,400	77,513
Stock option exercised (in shares)			0	0
2018 Equity Incentive Plan (the "2018 Plan") [Member] \| Stock Options [Member] \| Minimum [Member]
Stock-based compensation
Options granted, grant date fair value				$ 10.36
Stock awards vesting period			1 year
2018 Equity Incentive Plan (the "2018 Plan") [Member] \| Stock Options [Member] \| Maximum [Member]
Stock-based compensation
Options granted, grant date fair value				$ 12.13
Stock awards vesting period			4 years