Stock-based Compensation - Stock Option Activity (Details) - Stock Options - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Number Outstanding
Outstanding at end of period (in shares)	450,000
Exercisable at end of period (in shares)	360,000
Weighted Average Exercise Price
Outstanding at end of period (in dollars per share)	$ 1.62
Exercisable at end of period (in dollars per share)	$ 1.61
2018 LTIP
Number Outstanding
Outstanding at beginning of period (in shares)	455,000	537,500	537,500
Forfeited or expired during period (in shares)	(5,000)	(82,500)
Outstanding at end of period (in shares)	450,000	455,000	455,000
Exercisable at end of period (in shares)	360,000	185,000
Weighted Average Exercise Price
Outstanding at beginning of period (in dollars per share)	$ 1.67	$ 2.19	$ 2.19
Forfeited or expired during period (in dollars per share)	6.00	4.89
Outstanding at end of period (in dollars per share)	1.62	1.67	$ 1.67
Exercisable at end of period (in dollars per share)	$ 1.62	$ 1.74
Additional disclosures
Stock based compensation expense (reversal of expense)	$ 9	$ 9
Unrecognized compensation cost, options	$ 35
Period for recognizing unrecognized compensation cost	11 years

Amount, after tax, of expense for award under share-based payment arrangement.

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

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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- Definition

For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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Weighted average price of options that were either forfeited or expired.

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Number of options outstanding, including both vested and non-vested options.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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