Note 9 - Subsequent Events (Details Textual) - Subsequent Event [Member] $ / shares in Units, $ in Millions	Oct. 22, 2018 USD ($) $ / shares
Dividends Payable, Amount Per Share \| $ / shares	$ 0.27
Dividends Payable \| $	$ 5.6
Dividends Payable, Date Declared	Oct. 22, 2018
Dividends Payable, Date of Record	Nov. 05, 2018
Dividends Payable, Date to be Paid	Nov. 16, 2018

Date the declared dividend will be paid, in CCYY-MM-DD format.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
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The per share amount of a dividend declared, but not paid, as of the financial reporting date.

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Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(24))
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-Name Accounting Standards Codification
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-Topic 944
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Date the dividend to be paid was declared, in CCYY-MM-DD format.

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Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

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