Note 10 - Stock Based Compensation (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended	132 Months Ended
Dec. 31, 2014	Dec. 31, 2014
Common Class A [Member] \| Two Thousand Thirteen Stock Incentive Plan [Member]
Note 10 - Stock Based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	1,604,410	1,604,410
Restricted Stock [Member] \| Maximum [Member] \| Two Thousand Thirteen Stock Incentive Plan [Member]
Note 10 - Stock Based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	4 years
Time Vesting RSU [Member] \| Two Thousand Thirteen Stock Incentive Plan [Member]
Note 10 - Stock Based Compensation (Details) [Line Items]
Stock Issued During Period, Shares, Restricted Stock Award, Gross	51,343
Performance and Time Vesting RSUs [Member] \| Two Thousand Thirteen Stock Incentive Plan [Member]
Note 10 - Stock Based Compensation (Details) [Line Items]
Stock Issued During Period, Shares, Restricted Stock Award, Gross	33,612
Performance and Time Vesting RSUs [Member]
Note 10 - Stock Based Compensation (Details) [Line Items]
Estimated Allocated Share Based Compensation Expense	100.00%
Employee Stock Option [Member] \| Maximum [Member] \| Two Thousand Thirteen Stock Incentive Plan [Member]
Note 10 - Stock Based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	5 years
Employee Stock Option [Member] \| Two Thousand Thirteen Stock Incentive Plan [Member]
Note 10 - Stock Based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	10 years	6 years
Employee Stock Option [Member]
Note 10 - Stock Based Compensation (Details) [Line Items]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options (in Dollars)	7.9	7.9
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	1 year 6 months
Net of Discount [Member] \| The2009 ESPP [Member]
Note 10 - Stock Based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Per Share Weighted Average Price of Shares Purchased (in Dollars per share)	67.56	67.56
Per Share Discount [Member] \| The2009 ESPP [Member]
Note 10 - Stock Based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Per Share Weighted Average Price of Shares Purchased (in Dollars per share)	11.92	11.92
The2009 ESPP [Member]
Note 10 - Stock Based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	1,500,000	1,500,000
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Rate	10.00%	10.00%
Share Based Compensation Arrangement by Share Based Payment Award Maximum Amount of Stock Per Employee	25,000
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent	85.00%
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period	64,817
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	539,471	539,471
Share-based Compensation Arrangement by Share-based Payment Award, Discount from Market Price, Offering Date	15.00%
Two Thousand Thirteen Stock Incentive Plan [Member]
Note 10 - Stock Based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	3,800,000	3,800,000

Represents the estimated expense recognized during the period arising from equity-based compensation arrangements.

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The amount of stock an employee can purchase under the plan per period.

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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.

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Unrecognized cost of unvested options awarded to employees as compensation.

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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.

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Discount rate from fair value on offering date that participants pay for shares.

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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.

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

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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).

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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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The weighted average of per share prices paid for shares purchased on the open market for issuance to employees under the plan.

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Number of share instruments newly issued under a share-based compensation plan.

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

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