Note 11 - Stock Based Compensation and Other Benefit Plans (Detail) (USD $)	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures (in Shares)	1,438,158
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Total Intrinsic Value	$ 1,000,000	$ 2,500,000	$ 1,900,000
Proceeds from Stock Options Exercised	1,100,000	3,600,000	3,600,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in Shares)	1,438,158
Defined Contribution Plan, Maximum Annual Contribution Per Employee, Percent	50.00%
Defined Contribution Plan, Employer Discretionary Contribution Amount	3,300,000	2,800,000	1,700,000
Participants' Contributions up to 3% of Compensation [Member]
Defined Contribution Plan, Employer Matching Contribution, Percent	3.00%
Employer Matching Percentage on Participants' Contributions	100.00%
Participants' Contributions from 3% to 6% of Compensation [Member]
Defined Contribution Plan, Employer Matching Contribution, Percent	6.00%
Employer Matching Percentage on Participants' Contributions	50.00%
Stock Options [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Stock Options [Member]
Share Based Compensation Arrangement, By Share Based Payment Award Options Granted Term	10 years
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate	0.00%
Cash Settled Stock Appreciation Right [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in Shares)	0
Per Share Value Used For Calculating Cash Settlement of Stock Appreciation Rights (in Dollars per share)	$ 7.89
Fair Market Value of Other Than Stock Option (in Dollars per share)	$ 1.20
Liability of Other Than Stock Option	300,000
Stock Options and Cash-settled Stock Appreciation Rights [Member]
Allocated Share-based Compensation Expense	2,300,000	2,100,000	1,800,000
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense	300,000	800,000	600,000
Performance Based Restricted Stock Units and Cash Settled Performance Based Restricted Stock Units [Member]
Allocated Share-based Compensation Expense	0	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in Shares)	0	0	0
Restricted Stock [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Restricted Stock [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	4 years
Restricted Stock [Member]
Allocated Share-based Compensation Expense	4,600,000	2,800,000	1,800,000
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense	900,000	1,100,000	600,000
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized	9,200,000
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition	2 years 109 days
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Total Fair Value	$ 2,500,000	$ 3,200,000	$ 1,200,000
2003 Long-Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Requisite Service Period	3 years
Share-based Compensation Arrangement, By Share Based Payment Award, Number of Shares Available for Issuance After Amendment (in Shares)	50,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in Shares)	1,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in Shares)	65,106
2004 Non-Employee Directors' Incentive Compensation Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in Shares)	247,973
Share Based Compensation Arrangement, By Share Based Payment Award Value of Restricted Shares Issued In Period (in Shares)	130,000
2006 Equity Incentive Plan [Member]
Share-based Compensation Arrangement, By Share Based Payment Award, Number of Shares Available for Issuance After Amendment (in Shares)		8,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in Shares)	1,363,315
Share Based Compensation Arrangement, By Share Based Payment Award, Number Of Shares Authorized Before Amendment (in Shares)		5,000,000

Employer Matching Percentage on Participants' Contributions.

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- Definition

Fair market value of other than stock option.

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Share-based Compensation Arrangement, By Share Based Payment Award, Number of Shares Available for Issuance After Amendment.

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Share based compensation arrangement by share based payment award value of restricted shares issued in period.

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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

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-SubTopic 10

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

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-Name Statement of Financial Accounting Standard (FAS)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 6: http://www.xbrl.org/2003/role/presentationRef

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- Definition

Amount of discretionary contributions made by an employer to a defined contribution plan.

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Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

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Maximum percentage of employee gross pay, by the terms of the plan, that the employer may contribute to a defined contribution plan.

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- Definition

As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

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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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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the 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 Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph i

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 18

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Paragraph 2

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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

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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- 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 total fair value of equity-based awards for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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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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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.

+ References

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

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-SubTopic 10

-Section 50

-Paragraph 2

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The total accumulated difference between fair values of underlying shares on dates of exercise and exercise price on options which were exercised (or share units converted) into shares during the reporting period under the plan.

+ References

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

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

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