Note 10 - Subsequent Events (Details Textual) - Subsequent Event [Member] $ / shares in Units, $ in Millions	Oct. 25, 2018 USD ($) $ / shares
Common Stock, Dividends, Per Share, Declared \| $ / shares	$ 2
Dividends, Common Stock, Total \| $	$ 52
Dividends Payable, Date to be Paid	Dec. 10, 2018
Dividends Payable, Date of Record	Nov. 15, 2018

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

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586

+ 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://fasb.org/us-gaap/role/ref/legacyRef
-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://fasb.org/us-gaap/role/ref/legacyRef
-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

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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