Note 7 - Income Taxes (Details) - Unrecongnized Tax Benefits (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Unrecongnized Tax Benefits [Abstract]
Beginning balance	$ 29.7us-gaap_UnrecognizedTaxBenefits	$ 25.8us-gaap_UnrecognizedTaxBenefits	$ 17.4us-gaap_UnrecognizedTaxBenefits
Ending balance	31.6us-gaap_UnrecognizedTaxBenefits	29.7us-gaap_UnrecognizedTaxBenefits	25.8us-gaap_UnrecognizedTaxBenefits
Additions based on tax positions related to the current year	8.2	7.0	7.1
Additions/(reductions) based on tax positions taken in prior years	0.4	(1.2)	4.2
Reductions due to settlements	(3.7)	(0.1)
Reductions due to lapse of applicable statute of limitations	$ (3.0)	$ (1.8)	$ (2.9)

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Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

-URI http://asc.fasb.org/extlink&oid=6527854

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

-Subparagraph (a)

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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

-Subparagraph (a)(2)

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

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-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

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