Note 8 - Fair Value Measurements (Details) - Summary of Fair Value Measurements by Level (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Note 8 - Fair Value Measurements (Details) - Summary of Fair Value Measurements by Level [Line Items]
Cash and cash equivalents	$ 69,767	$ 81,705
Restricted cash and cash equivalents	10,651	13,929
Available for sale securities	290,808us-gaap_AvailableForSaleSecurities	247,012us-gaap_AvailableForSaleSecurities
Total financial assets	371,226us-gaap_AssetsFairValueDisclosure	342,646us-gaap_AssetsFairValueDisclosure
Equity Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Note 8 - Fair Value Measurements (Details) - Summary of Fair Value Measurements by Level [Line Items]
Available for sale securities	132,535	105,009
Equity Securities [Member]
Note 8 - Fair Value Measurements (Details) - Summary of Fair Value Measurements by Level [Line Items]
Available for sale securities	132,535	105,009
Corporate Debt Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Note 8 - Fair Value Measurements (Details) - Summary of Fair Value Measurements by Level [Line Items]
Available for sale securities	39,909
Corporate Debt Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Note 8 - Fair Value Measurements (Details) - Summary of Fair Value Measurements by Level [Line Items]
Available for sale securities	29,007	65,006
Corporate Debt Securities [Member]
Note 8 - Fair Value Measurements (Details) - Summary of Fair Value Measurements by Level [Line Items]
Available for sale securities	68,916	65,006
Commercial Mortgage Backed Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Note 8 - Fair Value Measurements (Details) - Summary of Fair Value Measurements by Level [Line Items]
Available for sale securities	63,252	45,856
Commercial Mortgage Backed Securities [Member]
Note 8 - Fair Value Measurements (Details) - Summary of Fair Value Measurements by Level [Line Items]
Available for sale securities	63,252	45,856
US Treasury Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Note 8 - Fair Value Measurements (Details) - Summary of Fair Value Measurements by Level [Line Items]
Available for sale securities	14,728	22,841
US Treasury Securities [Member]
Note 8 - Fair Value Measurements (Details) - Summary of Fair Value Measurements by Level [Line Items]
Available for sale securities	14,728	22,841
US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Note 8 - Fair Value Measurements (Details) - Summary of Fair Value Measurements by Level [Line Items]
Available for sale securities	2,216
US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Note 8 - Fair Value Measurements (Details) - Summary of Fair Value Measurements by Level [Line Items]
Available for sale securities	9,161	8,300
US States and Political Subdivisions Debt Securities [Member]
Note 8 - Fair Value Measurements (Details) - Summary of Fair Value Measurements by Level [Line Items]
Available for sale securities	11,377	8,300
Fair Value, Inputs, Level 1 [Member]
Note 8 - Fair Value Measurements (Details) - Summary of Fair Value Measurements by Level [Line Items]
Cash and cash equivalents	69,767	81,705
Restricted cash and cash equivalents	10,651	13,929
Total financial assets	269,806	223,484
Fair Value, Inputs, Level 2 [Member]
Note 8 - Fair Value Measurements (Details) - Summary of Fair Value Measurements by Level [Line Items]
Total financial assets	$ 101,420	$ 119,162

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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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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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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-Publisher FASB

-Name Accounting Standards Codification

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The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. This element is for unclassified presentations; for classified presentations there is a separate and distinct element.

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-Publisher SEC

-Name Regulation S-X (SX)

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