Note 15 - Dividends and Dividend Equivalents (Details Textual) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Common Stock, Dividends, Per Share, Declared	$ 0.20	$ 0.20
Dividends, Common Stock	$ 8.2	$ 8.0
Dividends Payable, Current	8.2		$ 8.2
Accrued Dividend Equivalents	$ 4.9		$ 4.1

Amount of dividend equivalents accrued during the period.

No definition available.

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- Definition

Aggregate dividends declared during the period for each share of common stock outstanding.

+ References

+ Details

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- Definition

Amount of paid and unpaid common stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 405
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6957935&loc=d3e64057-112817

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- Definition

Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=82887183&loc=d3e6935-107765

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.20)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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