Note 11 - Marketable Securities - Marketable Securities (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Amortized Cost - Equity securities	$ 13,072	$ 6,096
Gross Unrealized Gains - Equity securities	(1,136)	406
Marketable equity securities	11,936	6,502
Amortized Cost - Debt securities	1,329	1,599
Gross Unrealized Gains - Debt securities
Estimated Fair Value - Debt securities	1,329	1,599
Amortized Cost - Total marketable securities	14,401	7,695
Gross Unrealized Gains - Total marketable securities	(1,136)	406
Estimated Fair Value - Total marketable securities	$ 13,265	$ 8,101

Amount of accumulated unrealized gain (loss) on investments in debt securities classified as held-to-maturity.

No definition available.

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- Definition

Amount of accumulated unrealized gain (loss) on investments in debt securities classified as marketable securities.

+ References

No definition available.

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The item represents the total cost of debt and equity securities, including: (1) securities held-to-maturity, (2) trading securities, and (3) securities available-for-sale.

+ References

No definition available.

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Represents the fair value of marketable securities.

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No definition available.

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- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Amount before tax of unrealized gain (loss) in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

No definition available.

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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

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Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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Fair value of investments in debt securities classified as held-to-maturity.

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