9. Non-Cash Share-Based Employee Compensation (Details) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($) $ / shares shares
Compensation Related Costs [Abstract]
Outstanding Stock Options, beginning \| shares	460,500
Vested Stock Options, beginning \| shares	156,900
Nonvested Stock Options, beginning \| shares	303,600
Issued Stock Options \| shares	90,000
Exercised Stock Options \| shares	1,000
Forfeited Stock Options \| shares	12,500
Expired Stock Options \| shares	0
Outstanding Stock Options, ending \| shares	537,000
Vested Stock Options, ending \| shares	198,800
Nonvested Stock Options, ending \| shares	338,200
Outstanding Wgt. Avg. Exercise Price, beginning	$ 4.22
Vested Wgt. Avg. Exercise Price, beginning	4.03
Nonvested Wgt. Avg. Exercise Price, beginning	4.32
Issued Wgt. Avg. Exercise Price	4.07
Exercised Wgt. Avg. Exercise Price	1.89
Forfeited Wgt. Avg. Exercise Price	5.10
Expired Wgt. Avg. Exercise Price	.00
Outstanding Wgt. Avg. Exercise Price, ending	4.18
Vested Wgt. Avg. Exercise Price, ending	4.14
Nonvested Wgt. Avg. Exercise Price, ending	$ 4.20
Outstanding Contractual Life	7 years 4 months 2 days
Vested Contractual Life	4 years 7 months 28 days
Nonvested Contractual Life	8 years 10 months 28 days
Outstanding Grant Date Fair Value, beginning	$ 1.76
Vested Grant Date Fair Value, beginning	2.05
Nonvested Grant Date Fair Value, beginning	1.61
Issued Grant Date Fair Value	1.62
Exercised Grant Date Fair Value	0.71
Forfeited Grant Date Fair Value	1.37
Expired Grant Date Fair Value	.00
Outstanding Grant Date Fair Value	1.83
Vested Grant Date Fair Value	1.95
Nonvested Grant Date Fair Value	$ 1.76
Outstanding Aggregate Intrinsic Value \| $	$ 0
Vested Aggregate Intrinsic Value \| $	$ 0
Nonvested Aggregate Intrinsic Value	$ 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 \| $	$ 155,100
Vested Aggregate Intrinsic Value \| $	$ 74,420
Nonvested Aggregate Intrinsic Value	$ 80,680

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

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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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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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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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