Note 3 - Accumulated Other Comprehensive Income (Details) - Changes in Accumulated Other Comprehensive Income by Component (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	$ 497	$ 5,982	$ (3,212)	$ 6,869
Other comprehensive income (loss) before reclassifications	4,973	(10,250)	8,577	(11,188)
Amounts reclassified from accumulated other comprehensive income	8	4	113	55
Net current-period other comprehensive income (loss)	4,981	(10,246)	8,690	(11,133)
Ending balance	5,478	(4,264)	5,478	(4,264)
Accumulated Net Unrealized Investment Gain (Loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	63	8,480	(3,623)	9,411
Other comprehensive income (loss) before reclassifications	4,973	(10,250)	8,577	(11,188)
Amounts reclassified from accumulated other comprehensive income	(15)	(40)	67	(33)
Net current-period other comprehensive income (loss)	4,958	(10,290)	8,644	(11,221)
Ending balance	5,021	(1,810)	5,021	(1,810)
Accumulated Defined Benefit Plans Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	434	(2,498)	411	(2,542)
Other comprehensive income (loss) before reclassifications	0	0	0	0
Amounts reclassified from accumulated other comprehensive income	23	44	46	88
Net current-period other comprehensive income (loss)	23	44	46	88
Ending balance	$ 457	$ (2,454)	$ 457	$ (2,454)