Note 6 - Interest Rate Swap Derivatives - Pre-tax Net Gains (Losses) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2017	Dec. 31, 2016
Amount of pre-tax gain (loss) recognized in OCI	$ 463	$ (692)
Effective portion reclassified from AOCI into income	(578)	(2,255)
Ineffective portion recognized in income on derivatives	(1)	1
Interest Rate Swap 1 [Member]
Amount of pre-tax gain (loss) recognized in OCI	100	(197)
Effective portion reclassified from AOCI into income	(154)	(628)
Ineffective portion recognized in income on derivatives
Interest Rate Swap 2 [Member]
Amount of pre-tax gain (loss) recognized in OCI	35	(514)
Effective portion reclassified from AOCI into income	(231)	(880)
Ineffective portion recognized in income on derivatives
Interest Rate Swap 3 [Member]
Amount of pre-tax gain (loss) recognized in OCI	328	19
Effective portion reclassified from AOCI into income	(193)	(747)
Ineffective portion recognized in income on derivatives	$ (1)	$ 1

The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4D
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624177-113959

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- Definition

The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 25
-Section 50
-Paragraph 1
-Subparagraph (a)(1),(2)
-URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986

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- Definition

The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

+ References

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