The annual increments to be vested in common stock units, as a percentage.

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- Definition

The expense resulting from the benefit (short-fall) of tax deductions from share-based compensation, in excess of grant-date fair value.

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The maximum period of common stock granted.

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- Definition

The number of officers receiving a share-based compensation award.

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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
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-SubTopic 10
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- Definition

Unrecognized cost of unvested share-based compensation awards.

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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

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.

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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 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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- 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

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

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No definition available.

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

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Note 5 - Stock-based Compensation (Details)	1 Months Ended		3 Months Ended		12 Months Ended
Note 5 - Stock-based Compensation (Details)	Dec. 31, 2015 shares	Dec. 31, 2014 shares	Mar. 31, 2016 USD ($) shares	Mar. 31, 2015 USD ($) shares	Dec. 31, 2015 $ / shares shares	Dec. 31, 2013 shares
Note 5 - Stock-based Compensation (Details) [Line Items]
Maximum Period of Common Stock Granted			10 years
Annual Increments to Be Vested in Common Stock Units			20.00%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross \| shares			0	0
Allocated Share-based Compensation Expense (in Dollars)			$ 0	$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period \| shares			2,110	3,750
Proceeds from Stock Options Exercised (in Dollars)			$ 49,000	$ 88,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value (in Dollars)			9,000	10,000
Benefit (Shortfall) of Tax Deductions from Share-based Compensation (in Dollars)			(3,298,000)	(4,395,000)
Additional Paid-in Capital [Member]
Note 5 - Stock-based Compensation (Details) [Line Items]
Benefit (Shortfall) of Tax Deductions from Share-based Compensation (in Dollars)			$ 140,000
2005 Incentive Plan [Member]
Note 5 - Stock-based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized \| shares			3,789,782
Restricted Stock Units (RSUs) [Member]
Note 5 - Stock-based Compensation (Details) [Line Items]
Allocated Share-based Compensation Expense (in Dollars)			$ 1,000,000	$ 1,100,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period \| shares			0		37,675
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value (in Dollars per share) \| $ / shares					$ 27.53
Number of Officers Receiving Award	7	7				8
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized (in Dollars)			$ 6,500,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition			2 years 73 days
Performance TSR Restricted Stock [Member]
Note 5 - Stock-based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period \| shares	61,209	60,456				119,840
Performance EPS Restricted Stock Units [Member]
Note 5 - Stock-based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period \| shares	57,409	57,642				116,186