Note 7 - Stock-Based Compensation (Details) - Summary of Outstanding and Exercisable Options (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Shares Outstanding (in Shares)	590
Weighted-Average Remaining Contractual Term	1 year 73 days
Weighted Average Exercise Price	$ 15.80
Shares Outstanding, Exercisable (in Shares)	568
Weighted Average Exercise Price, Exercisable	$ 15.92
Range 01 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercises Prices, Upper	$ 0.76
Range of Exercises Prices, Lower	$ 14.96
Shares Outstanding (in Shares)	118
Weighted-Average Remaining Contractual Term	2 years
Weighted Average Exercise Price	$ 12.16
Shares Outstanding, Exercisable (in Shares)	98
Weighted Average Exercise Price, Exercisable	$ 12.07
Range 02 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercises Prices, Upper	$ 15.03
Range of Exercises Prices, Lower	$ 15.03
Shares Outstanding (in Shares)	321
Weighted-Average Remaining Contractual Term	292 days
Weighted Average Exercise Price	$ 15.03
Shares Outstanding, Exercisable (in Shares)	321
Weighted Average Exercise Price, Exercisable	$ 15.03
Range 03 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercises Prices, Upper	$ 15.13
Range of Exercises Prices, Lower	$ 23.50
Shares Outstanding (in Shares)	151
Weighted-Average Remaining Contractual Term	1 year 219 days
Weighted Average Exercise Price	$ 20.29
Shares Outstanding, Exercisable (in Shares)	149
Weighted Average Exercise Price, Exercisable	$ 20.36

Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

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The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

+ 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 (c)(iii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

+ 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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-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

+ References

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-Publisher FASB

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Weighted average remaining contractual term of outstanding stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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

-Publisher FASB

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The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

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

-Publisher FASB

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