Note 3 - Accumulated Other Comprehensive Income - Changes in Accumulated Other Comprehensive Income by Component (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Beginning balance	$ 184,066	$ 175,698
Net current-period other comprehensive income	1,013	2,642
Ending balance	187,740	184,052
Accumulated Net Investment Gain (Loss) Attributable to Parent [Member]
Beginning balance	(3,363)	3,219
Other comprehensive income before reclassifications	948	2,687
Amounts reclassified from accumulated other comprehensive income	6	(54)
Net current-period other comprehensive income	954	2,633
Ending balance	(2,409)	5,852
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Beginning balance	(45)	(437)
Other comprehensive income before reclassifications	10	0
Amounts reclassified from accumulated other comprehensive income	49	9
Net current-period other comprehensive income	59	9
Ending balance	14	(428)
AOCI Attributable to Parent [Member]
Beginning balance	(3,408)	2,782
Other comprehensive income before reclassifications	958	2,687
Amounts reclassified from accumulated other comprehensive income	55	(45)
Net current-period other comprehensive income	1,013	2,642
Ending balance	$ (2,395)	$ 5,424

Amount after tax, before reclassification adjustments, of other comprehensive income (loss), attributable to parent.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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