Number of nonvested restricted shares outstanding.

No definition available.

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- Definition

Gross number of share options (or share units) granted for plan to date.

+ References

No definition available.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of options which vested during the period.

+ References

No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 14.F)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 14
-Section F

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Disclosure of the aggregate tax benefit realized from the exercise of stock options and the conversion of similar instruments during the annual period.

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- Definition

The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (j)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3255-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

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- Definition

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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

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- Definition

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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- Definition

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.

+ References

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- Definition

Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

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-Topic 505
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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Note 9 - Share-Based Compensation (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
The 2001 Equity Incentive Plan [Member] \| Common Class A [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	1,800,000
Share-based Compensation Arrangement by Share-based Payment Award, Options Grants Cumulative	1,683,309
The 2001 Equity Incentive Plan [Member] \| Common Class B [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	300,000
Share-based Compensation Arrangement by Share-based Payment Award, Options Grants Cumulative	280,552
The 2001 Equity Incentive Plan [Member] \| Employee Stock Option [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	1 year
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	5 years
The 2001 Equity Incentive Plan [Member] \| Employee Stock Option [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	5 years
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	10 years
The 2001 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	0
Director Plan 2004 [Member] \| Common Class A [Member] \| Nonqualified Stock Options [Member] \| Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	36,000
Director Plan 2004 [Member] \| Common Class A [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	1,245,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	3,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Options Grants Cumulative	1,755,000
Director Plan 2004 [Member] \| Common Class B [Member] \| Nonqualified Stock Options [Member] \| Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	6,000
Director Plan 2004 [Member] \| Common Class B [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	207,500
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	500,000
Share-based Compensation Arrangement by Share-based Payment Award, Options Grants Cumulative	292,500
Director Plan 2004 [Member] \| Nonqualified Stock Options [Member] \| Minimum [Member] \| Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	3 years
Director Plan 2004 [Member] \| Nonqualified Stock Options [Member] \| Maximum [Member] \| Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	10 years
Director Plan 2004 [Member] \| Nonqualified Stock Options [Member] \| Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	1 year
The 2006 Equity Incentive Plan [Member] \| Common Class A [Member] \| Nonvested [Member]
Stock Issued During Period, Shares, Restricted Stock Award, Gross	89,416	73,506
Share-based Compensation Arrangement by Share-based Payment Award, Nonvested Restricted Stock, Outstanding Number	183,814
The 2006 Equity Incentive Plan [Member] \| Common Class A [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	1,044,778
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	1,800,000
Share-based Compensation Arrangement by Share-based Payment Award, Options Grants Cumulative	755,222
The 2006 Equity Incentive Plan [Member] \| Common Class B [Member] \| Nonvested [Member]
Stock Issued During Period, Shares, Restricted Stock Award, Gross	14,902	12,251
Share-based Compensation Arrangement by Share-based Payment Award, Nonvested Restricted Stock, Outstanding Number	30,635
The 2006 Equity Incentive Plan [Member] \| Common Class B [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	175,075
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	300,000
Share-based Compensation Arrangement by Share-based Payment Award, Options Grants Cumulative	124,925
The 2006 Equity Incentive Plan [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	5 years
The 2006 Equity Incentive Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	10 years
Common Class A [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	261,306	204,166	232,344
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 3.49	$ 2.14
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value	$ 350,000	$ 1,500,000	$ 1,100,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Period Vested, Aggregate Intrinsic Value	1,400,000	$ 528,000	$ 1,500,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized	$ 595,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	2 years 14 days
Common Class B [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	43,551	32,217	38,718
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 5.45	$ 2.16
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value	$ 151,000	$ 502,000	$ 992,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Period Vested, Aggregate Intrinsic Value	415,000	402,000	$ 514,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized	$ 139,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	2 years 36 days
Common Class A and Class B [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value			$ 3.24
Employee Stock Option [Member] \| Selling, General and Administrative Expenses [Member]
Allocated Share-based Compensation Expense	$ 828,000	707,000	$ 815,000
Nonvested [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	1 year
Nonvested [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	5 years
Nonvested [Member] \| Selling, General and Administrative Expenses [Member]
Allocated Share-based Compensation Expense	$ 555,000	35,000	140,000
Nonvested [Member]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized	$ 2,500,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	3 years 76 days
Proceeds from Stock Options Exercised	$ 0	408,000	840,000
Employee Service Share-based Compensation, Tax Benefit Realized from Exercise of Stock Options	$ 217,000	$ 622,000	$ 753,000