Note 7 - Investments in Marketable Securities - Marketable Securities and Restricted Marketable Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Restricted investments available for sale, amortized cost	$ 185,968	$ 171,174
Investments available for sale, amortized cost	216,144	201,350
Available-for-sale securities	321,717	286,034
Equity Securities [Member]
Unrestricted investments available for sale, amortized cost	30,176	30,176
Unrestricted investments available for sale, fair value	138,013	116,168
Corporate Debt Securities [Member]
Restricted investments available for sale, amortized cost	71,311	71,960
Restricted investments available for sale, fair value	71,100	71,143
Asset-backed Securities [Member]
Restricted investments available for sale, amortized cost	56,889	61,645
Restricted investments available for sale, fair value	56,168	60,910
US Government Corporations and Agencies Securities [Member]
Restricted investments available for sale, amortized cost	25,748	21,123
Restricted investments available for sale, fair value	25,181	21,033
US States and Political Subdivisions Debt Securities [Member]
Restricted investments available for sale, amortized cost	32,020	16,446
Restricted investments available for sale, fair value	$ 31,255	$ 16,780

This item represents the cost of debt 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.

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

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Amount of investments in equity securities and other forms of securities that provide ownership interests classified as available-for-sale, expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer.

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Total debt and equity financial instruments including: (1) securities held-to-maturity, (2) trading securities, and (3) securities available-for-sale that are pledged to one or more secured parties who have the right to buy, sell, or re-pledge the collateral.

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