Note 8 - Recently Adopted Accounting Pronouncements (Details Textual) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2017	Dec. 31, 2016	Mar. 31, 2016
Adjustments for New Accounting Principle, Early Adoption [Member]
Tax Adjustments, Settlements, and Unusual Provisions	$ 2.1	$ 4.8	$ 2.3

Amount of increase (decrease) to previously recorded tax expense. Includes, but is not limited to, significant settlements of income tax disputes, and unusual tax positions or infrequent actions taken by the entity, including tax assessment reversal, and IRS tax settlement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 25
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=96869850&loc=d3e28446-109314

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 25
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=96869850&loc=d3e28511-109314

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Period Type:	duration