9. Non-Cash Share-Based Employee Compensation (Details) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2017 USD ($) $ / shares shares
Notes to Financial Statements
Outstanding Stock Options, beginning \| shares	311,000
Vested Stock Options, beginning \| shares	231,000
Nonvested Stock Options, beginning \| shares	80,000
Issued Stock Options \| shares	178,500
Exercised Stock Options \| shares	125,000
Forfeited Stock Options \| shares	60,000
Expired Stock Options \| shares	0
Outstanding Stock Options, ending \| shares	304,500
Vested Stock Options, ending \| shares	108,000
Nonvested Stock Options, ending \| shares	196,500
Outstanding Wgt. Avg. Exercise Price, beginning	$ 3.48
Vested Wgt. Avg. Exercise Price, beginning	3.30
Nonvested Wgt. Avg. Exercise Price, beginning	4.01
Issued Wgt. Avg. Exercise Price	5.10
Exercised Wgt. Avg. Exercise Price	2.88
Forfeited Wgt. Avg. Exercise Price	3.95
Expired Wgt. Avg. Exercise Price	0
Outstanding Wgt. Avg. Exercise Price, ending	4.58
Vested Wgt. Avg. Exercise Price, ending	3.80
Nonvested Wgt. Avg. Exercise Price, ending	$ 5.02
Outstanding Contractual Life	7 years 5 months 13 days
Vested Contractual Life	3 years 9 months 7 days
Nonvested Contractual Life	9 years 6 months
Outstanding Grant Date Fair Value, beginning	$ 1.96
Vested Grant Date Fair Value, beginning	1.97
Nonvested Grant Date Fair Value, beginning	1.93
Issued Grant Date Fair Value	1.36
Exercised Grant Date Fair Value	1.62
Forfeited Grant Date Fair Value	2.03
Expired Grant Date Fair Value	0
Outstanding Grant Date Fair Value	1.73
Vested Grant Date Fair Value	2.37
Nonvested Grant Date Fair Value	$ 1.38
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 \| $	$ 150,960
Vested Aggregate Intrinsic Value \| $	$ 136,850
Nonvested Aggregate Intrinsic Value	$ 14,110

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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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Per share weighted average intrinsic value of equity-based compensation awards not vested. Excludes stock 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 share instruments newly issued under a share-based compensation plan.

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Number of share options (or share units) exercised during the current period.

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