Note 4 - Goodwill and Other Intangible Assets - Changes in Gross Carrying Value of Other Intangible Assets and Goodwill (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016
Balance, beginning of year	$ 298,383	$ 298,394
Increase from acquisitions
Decrease from impairment charges
Balance, end of period	298,383	298,394
Balance, beginning of year	47,342	47,342
Increase from acquisitions
Decrease from impairment charges	(1,117)
Balance, end of period	$ 46,225	$ 47,342

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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-Name Accounting Standards Codification
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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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