9. Non-Cash Share-Based Employee Compensation (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Compensation Related Costs [Abstract]
Outstanding stock options	569,500
Vested stock options	214,800
Nonvested stock options	354,700
Issued stock options	0
Exercised stock options	0
Forfeited stock options	56,100
Expired stock options	65,000
Outstanding stock options	448,400	569,500
Vested stock options	201,400	214,800
Nonvested stock options	247,000	354,700
Outstanding wgt. avg. exercise price	$ 4.16
Vested wgt. avg. exercise price	4.12
Nonvested wgt. avg. exercise price	4.18
Issued wgt. avg. exercise price	.00
Exercised wgt. avg. exercise price	.00
Forfeited wgt. avg. exercise price	4.11
Expired wgt. avg. exercise price	4.07
Outstanding wgt. avg. exercise price	4.18	$ 4.16
Vested wgt. avg. exercise price	4.21	$ 4.12
Nonvested wgt. avg. exercise price	$ 4.15
Outstanding contractual life	7 years 4 months 2 days	6 years 9 months 25 days
Vested contractual life	6 years 2 months 19 days	4 years 2 months 12 days
Nonvested contractual life	8 years 3 months 4 days	8 years 4 months 24 days
Outstanding grant date fair value	$ 1.75
Vested grant date fair value	1.95
Nonvested grant date fair value	1.63
Issued grant date fair value	.00
Exercised grant date fair value	.00
Forfeited grant date fair value	1.74
Expired grant date fair value	2.88
Outstanding grant date fair value	1.59
Vested grant date fair value	1.55
Nonvested grant date fair value	$ 1.62
Outstanding aggregate intrinsic value	$ 0	$ 24,000
Vested aggregate intrinsic value	0	24,000
Nonvested aggregate intrinsic value	$ 0	0
Issued aggregate intrinsic value	$ 0
Exercised aggregate intrinsic value	$ 0
Forfeited aggregate intrinsic value	$ 0
Expired aggregate intrinsic value	$ 0
Outstanding aggregate intrinsic value	$ 0	0
Vested aggregate intrinsic value	0	0
Nonvested aggregate intrinsic value	$ 0	$ 0

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The weighted average fair value at grant date for nonvested equity-based awards issued 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 non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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The combined weighted average of the accumulated differences between the fair values on underlying shares and exercises prices to acquire such shares as of the grant date on options that were either forfeited or lapsed.

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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.

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

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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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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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