Note 12 - Dividends Declared (Details) - USD ($) $ in Thousands	Nov. 06, 2015	Aug. 10, 2015	May. 12, 2015	Feb. 11, 2015	Nov. 12, 2014	Aug. 14, 2014
Subsequent Event [Member]
Dividends Per Share of Common Stock (in dollars per share)	$ 0.44
Record Date	Nov. 30, 2015
Dividends, Cash	$ 18,208
Payment Date	Dec. 15, 2015
Dividends Per Share of Common Stock (in dollars per share)		$ 0.44	$ 0.44	$ 0.39	$ 0.39	$ 0.39
Record Date		Aug. 31, 2015	May 29, 2015	Feb. 27, 2015	Nov. 28, 2014	Aug. 29, 2014
Dividends, Cash		$ 18,179	$ 18,274	$ 16,236	$ 16,216	$ 16,299
Payment Date		Sep. 15, 2015	Jun. 16, 2015	Mar. 17, 2015	Dec. 16, 2014	Sep. 16, 2014

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

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Amount of paid and unpaid cash dividends declared for classes of stock, for example, but not limited to, common and preferred.

+ 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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The per share amount of a dividend declared, but not paid, as of the financial reporting date.

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- Definition

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

+ References

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