Note 2 - Fair Value Measurements (Detail) (USD $)	12 Months Ended					59 Months Ended
	Dec. 31, 2012	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2012
Available-for-sale Securities, Current	$ 25,876,000	$ 25,876,000	$ 38,956,000			$ 25,876,000
Deposits, Money Market Deposits	16,000,000	16,000,000	51,100,000			16,000,000
Available-for-sale Securities, Gross Realized Losses		7,000	17,000
Available-for-sale Securities	14,121,000	14,121,000	25,281,000			14,121,000
Cash Equivalents, at Carrying Value			2,000,000
Auction Rate Securities, Noncurrent	11,755,000	11,755,000	13,675,000	19,180,000		11,755,000
Proceeds from Sale of Available-for-sale Securities		2,100,000	5,800,000
Other than Temporary Impairment Losses, Investments		(140,000)	(270,000)	(160,000)
Investment Maturity Date		Dec. 31, 2008
Trading Securities, Realized Gain (Loss)					70,000
Percentage of Auction Rate Securities Redeemed at Par Value						68.00%
Credit Risk Evaluation Description	Based on the guidance of ASC 320-10-35 and ASC 320-10-50, the Company evaluated the potential credit loss of each of the auction-rate securities that are currently held by the Company. Based on such analysis, the Company determined that those securities that are not 100% FFELPS guaranteed are potentially subject to credit risks based on the extent to which the underlying debt is collateralized and the security-specific student-loan default rates. The Company's portfolio includes two such securities. The senior parity ratio for the two securities is approximately 106%. If, therefore, the student-loan default rate and borrowing rate increases for these issuers, the remaining balance in these trusts may not be sufficient to cover the senior debt. The Company therefore concluded that there is potential credit risk for these two securities and as such, used the discounted cash flow model to determine the amount of credit loss to be recorded. In valuing the potential credit loss, the following parameters were used: 2.0 year expected term, cash flows based on the 90-day t-bill rates for 2.0 year forwards and a risk premium of 5.9%, the amount of interest that the Company was receiving on these securities when the market was last active. During the year ended December 31, 2012, the Company was able to redeem a security at face value for which an OTTI of $40,000 had previously been recorded for and therefore, recognized a gain of $40,000 in interest income and other, net, in our Consolidated Statement of Operations.
Cash Flow Model Input Time To Liquidity	24	24	24			24
Cash Flow Model Input Expected Return	1.80%	1.80%	1.80%			1.80%
Government Backed Securities [Member]
Available-for-sale Securities, Current			77,800,000
Fair Value [Member] | Auction Rate Securities [Member]
Available-for-sale Securities	11,800,000	11,800,000				11,800,000
Government Backed Securities [Member]
Auction Rate Securities, Noncurrent	11,800,000	11,800,000				11,800,000
Auction Rate Securities Backed By Student-Loan Notes [Member]
Other than Temporary Impairment Losses, Investments		520,000
Temporary [Member]
Other than Temporary Impairment Losses, Investments		490,000	600,000
Other Than Temporary [Member]
Other than Temporary Impairment Losses, Investments		30,000	100,000
Auction Rate [Member]
Other than Temporary Impairment Losses, Investments			700,000
Moodys A3 To Baa3 [Member]
Auction Rate Securities, Noncurrent					6,300,000
Government Backed Securities [Member]
Available-for-sale Securities, Current	$ 85,500,000	$ 85,500,000				$ 85,500,000