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

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Amount of cost not yet recognized for nonvested award 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 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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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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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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Stock-Based Compensation (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	May 03, 2019
Share-based Payment Arrangement, Expense	$ 1,845	$ 2,001
Unrecognized compensation cost	$ 2,124
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 5.54	$ 6.17
2012 Plan [Member]
Shares available for grants	3,500,000
Stock Option Plan, Award Vesting Period	5 years
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	10 years
2019 Plan [Member]
Shares available for grants	2,735,169		3,000,000
Stock Option Plan, Award Vesting Period	5 years
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	10 years
Expected To Be Recognized During 2019 [Member]
Unrecognized compensation cost	$ 1,353
Expected To Be Recognized During 2020 [Member]
Unrecognized compensation cost	693
Expected To Be Recognized During 2021 [Member]
Unrecognized compensation cost	$ 78