Amounts contributed to Employee Stock Purchase Plans during the period.

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Percentage of the market value of shares held in the Employee Stock Purchase Plan.

+ References

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Number of substantially equal installments in which share-based payments will vest.

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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)

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-Section 50

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

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- Definition

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.

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- Definition

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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No definition available.

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

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No definition available.

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- Definition

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The number of grants made 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).

+ References

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- Definition

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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- Definition

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

+ References

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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- Definition

Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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- Definition

Number of additional shares authorized for issuance under an established share-based compensation plan.

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- Definition

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).

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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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- Definition

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.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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Note 9 - Stock-Based Compensation (Details)	1 Months Ended			9 Months Ended
Note 9 - Stock-Based Compensation (Details)	Mar. 31, 2015 shares	Feb. 28, 2015 shares	May. 31, 2011 USD ($) shares	Sep. 30, 2015 USD ($) shares	Sep. 30, 2014 USD ($) shares	Dec. 31, 2014 shares	Dec. 31, 2013 shares
Note 9 - Stock-Based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in Shares)				0	21,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value \| $				$ 10,600,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value \| $				8,500,000	$ 1,100,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value \| $				87,000	125,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options \| $				$ 69,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition				2 years 248 days
Allocated Share-based Compensation Expense \| $				$ 3,660,000	2,948,000
Virginia Heritage Plans [Member]
Note 9 - Stock-Based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in Shares)				0
The 1998 Stock Option Plan [Member]
Note 9 - Stock-Based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in Shares)				0
The Fidelity Plans [Member]
Note 9 - Stock-Based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in Shares)				0
2006 Stock Plan [Member]
Note 9 - Stock-Based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in Shares)				1,996,500
The 2011 ESPP [Member]
Note 9 - Stock-Based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in Shares)				437,727
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized (in Shares)			550,000
Employee Stock Purchase Plan, Percentage of Market Value			85.00%
Salaries and Employee Benefits [Member]
Note 9 - Stock-Based Compensation (Details) [Line Items]
Allocated Share-based Compensation Expense \| $				$ 3,700,000	$ 2,900,000
Performance Shares [Member]
Note 9 - Stock-Based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number (in Shares)				0
Restricted Stock [Member]
Note 9 - Stock-Based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in Shares)	700	77,370		78,070	78,947
Share-based Compensation Arrangement by Share-based Payment Award, Number of Vesting Periods	5	3
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number (in Shares)				387,753	507,774	509,336	614,580
Restricted Stock [Member] \| 2006 Stock Plan [Member]
Note 9 - Stock-Based Compensation (Details) [Line Items]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition				1 year 240 days
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number (in Shares)				387,753
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options \| $				$ 6,600,000
Minimum [Member] \| The 2011 ESPP [Member]
Note 9 - Stock-Based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Requisite Service Period			1 year
Minimum [Member] \| Pay Period [Member] \| The 2011 ESPP [Member]
Note 9 - Stock-Based Compensation (Details) [Line Items]
Amount Contributed To ESPP \| $			$ 10
Minimum Hours Per Week [Member] \| The 2011 ESPP [Member]
Note 9 - Stock-Based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Requisite Service Period			20 hours
Minimum Months Per Year [Member] \| The 2011 ESPP [Member]
Note 9 - Stock-Based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Requisite Service Period			5 months
Maximum [Member] \| The 2011 ESPP [Member]
Note 9 - Stock-Based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Rate			10.00%
Maximum [Member] \| Offering Period [Member] \| The 2011 ESPP [Member]
Note 9 - Stock-Based Compensation (Details) [Line Items]
Amount Contributed To ESPP \| $			$ 6,250
Maximum [Member] \| Annually [Member] \| The 2011 ESPP [Member]
Note 9 - Stock-Based Compensation (Details) [Line Items]
Amount Contributed To ESPP \| $			$ 25,000