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Note 10 - Developments in Accounting Pronouncements (Details Textual) - December 31, 2016 [Member] $ in Millions | 6 Months Ended
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Jun. 30, 2017 USD ($)
Reclassification of Deferred Tax Assets from Current to Noncurrent [Member] |
Prior Period Reclassification Adjustment | $ 12.3
Reclassification of Deferred Tax Liabilities from Current to Noncurrent [Member] |
Prior Period Reclassification Adjustment | $ 1.3

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