Note 2 - Cash and Cash Equivalents and Short-term Investments (Details) (USD $)	3 Months Ended	9 Months Ended
Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
Note 2 - Cash and Cash Equivalents and Short-term Investments (Details) [Line Items]
Cash, FDIC Insured Amount	$ 4,700,000		$ 4,700,000
Available-for-sale Equity Securities, Amortized Cost Basis	20,700,000		20,700,000		48,100,000
Proceeds from Sale of Available-for-sale Securities	322,000	7,700,000	28,929,000	22,396,000
Available-for-sale Securities, Gross Realized Gains	0	163,000	488,000	663,000
Available-for-sale Securities, Gross Realized Losses	11,000	0	16,000	0
Available-for-sale Securities, Gross Unrealized Gain (Loss)	311,000		1,400,000	492,000
Other Comprehensive Income (Loss), Tax			(114,000)
Investment Income, Interest	218,000	432,000	660,000	1,100,000
Municipal Bond Securities [Member]
Note 2 - Cash and Cash Equivalents and Short-term Investments (Details) [Line Items]
Available-for-sale Equity Securities, Amortized Cost Basis	20,700,000		20,700,000		20,500,000
Majority Owned Joint Ventures [Member]
Note 2 - Cash and Cash Equivalents and Short-term Investments (Details) [Line Items]
Restricted Cash and Cash Equivalents	$ 1,000,000		$ 1,000,000

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This item represents the cost of equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments for 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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No definition available.

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This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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Amount of unrealized gain (loss) on investments in debt and equity securities classified as available-for-sale securities.

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The amount of cash deposited in financial institutions as of the balance sheet date that is insured by the Federal Deposit Insurance Corporation.

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No definition available.

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Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

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Amount of tax expense (benefit) allocated to other comprehensive income (loss).

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The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities.

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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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