Note 5 - Income Taxes (Details Textual) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Effective Income Tax Rate Reconciliation, Percent	31.20%	36.30%
Unrecognized Tax Benefits	$ 1.2
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	1.0
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Amount of Unrecorded Benefit	$ 0.4
Internal Revenue Service (IRS) [Member] \| Earliest Tax Year [Member]
Open Tax Year	2013
Internal Revenue Service (IRS) [Member] \| Latest Tax Year [Member]
Open Tax Year	2016
State and Foreign Jurisdictions [Member] \| Earliest Tax Year [Member]
Open Tax Year	2013
State and Foreign Jurisdictions [Member] \| Latest Tax Year [Member]
Open Tax Year	2016

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h)(2))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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Tax year that remains open to examination under enacted tax laws, in CCYY format.

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The amount of the unrecognized tax benefit of a position taken for which it is reasonably possible that the total amount thereof will significantly increase or decrease within twelve months of the balance sheet date.

+ References

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Amount of unrecognized tax benefits.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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