Note 13 - Accumulated Other Comprehensive Income - Changes in Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Balance	$ (4,215)
Amounts reclassified from accumulated other comprehensive loss
Net current period other comprehensive income	1,508	$ 708
Balance	(2,707)
Accumulated Net Investment Gain (Loss) Attributable to Parent [Member] \| Available-for-sale Securities [Member]
Balance	(3,192)
Other comprehensive income before reclassifications	1,306
Net current period other comprehensive income	1,306
Balance	(1,886)
Accumulated Net Investment Gain (Loss) Attributable to Parent [Member] \| Auction Rate Securities [Member]
Balance	(1,023)
Other comprehensive income before reclassifications	202
Net current period other comprehensive income	202
Balance	(821)
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Balance	(4,215)
Other comprehensive income before reclassifications	1,508
Net current period other comprehensive income	1,508
Balance	$ (2,707)

Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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