Note 7 - Unrecongnized Tax Benefits (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Beginning balance	$ 31.6	$ 29.7	$ 25.8
Additions based on tax positions related to the current year	9.4	8.2	7.0
Additions/(reductions) based on tax positions taken in prior years	(2.5)	0.4	(1.2)
Reductions due to settlements	(3.0)	(3.7)	(0.1)
Reductions due to lapse of applicable statute of limitations	(3.5)	(3.0)	(1.8)
Ending balance	$ 32.0	$ 31.6	$ 29.7

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

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

Reference 2: 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

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

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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.

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

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

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