Note 9 - 401(k) Profit Sharing, Deferred Compensation and Long-term Incentive Plans (Details Textual) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Minimum [Member]
Deferred Compensation Arrangement with Individual, Requisite Service Period	1 year
Maximum [Member]
Deferred Compensation Arrangement with Individual, Requisite Service Period	7 years
Other Noncurrent Liabilities [Member]
Deferred Compensation Liability, Classified, Noncurrent	$ 19.7	$ 14.2
Defined Contribution Plan, Employer Discretionary Contribution Amount	$ 5.3	$ 3.2	$ 2.1

Minimum period the individual is required to perform services to be fully vested under the deferred compensation arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 710
-SubTopic 10
-Section 55
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6409961&loc=d3e20487-108367

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration