Assumptions used in fair value measurements.

No definition available.

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- Definition

Amount of securities that are debt instruments (corporate or municipal bonds) that typically have long-term nominal maturities for which the interest rate is reset through an auction process.

+ References

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

-Subparagraph (b)

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-Section 50

-Paragraph 5

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562

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- Definition

Amount of investment in debt and equity securities categorized neither as trading securities nor held-to-maturity securities and intended be sold or mature one year or operating cycle, if longer.

+ References

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- Definition

Amount of unrealized loss before deducting unrealized gain on investments in available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

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- Definition

Amount of deposits in accounts that offer many of the same services as checking accounts although transactions may be somewhat more limited, share some of the characteristics of a money market fund and are insured by the Federal government, also known as money market accounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.12)

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- Definition

The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Article 5

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-Topic 225

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-Paragraph 2

-Subparagraph (SX 210.5-03.7(b))

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- Definition

This item represents the gain (loss) realized during the period from the sale of trading securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

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-Subparagraph c

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-Glossary Trading Securities

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- Definition

Amount of unrealized holding gain (loss) recognized in the income statement for investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

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-Section S99

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-Subparagraph (SX 210.5-03.7(c))

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-Name Accounting Standards Codification

-Glossary Trading Securities

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Note 8 - Fair Value Measurements (Details) (USD $)	6 Months Ended		9 Months Ended	12 Months Ended
Note 8 - Fair Value Measurements (Details) (USD $)	Jun. 30, 2013	Jun. 30, 2012	Sep. 30, 2012	Dec. 31, 2012	Dec. 31, 2009	Mar. 31, 2013
Note 8 - Fair Value Measurements (Details) [Line Items]
Available-for-sale Securities	$ 115,323,000			$ 113,235,000
Deposits, Money Market Deposits	15,700,000			16,000,000
Available-for-sale Securities, Gross Unrealized Loss	541,000			497,000
Auction Rate Securities, Noncurrent	11,698,000			11,755,000	6,300,000	11,715,000
Trading Securities, Change in Unrealized Holding Gain (Loss)				7,000
Other than Temporary Impairment Losses, Investments	32,000	(99,000)		520,000
Trading Securities, Realized Gain (Loss)					70,000
Fair Value Input Expected Term			2 years
Investment Income, Interest				40,000
Government Backed Securities [Member]
Note 8 - Fair Value Measurements (Details) [Line Items]
Available-for-sale Securities	87,900,000
Temporary [Member]
Note 8 - Fair Value Measurements (Details) [Line Items]
Other than Temporary Impairment Losses, Investments	522,000			490,000
Other Than Temporary [Member]
Note 8 - Fair Value Measurements (Details) [Line Items]
Other than Temporary Impairment Losses, Investments	30,000			30,000
Auction Rate Securities Backed By Student-Loan Notes [Member]
Note 8 - Fair Value Measurements (Details) [Line Items]
Other than Temporary Impairment Losses, Investments	552,000
Face Value [Member]
Note 8 - Fair Value Measurements (Details) [Line Items]
Auction Rate Securities, Noncurrent	11,700,000
Government Backed Securities [Member]
Note 8 - Fair Value Measurements (Details) [Line Items]
Available-for-sale Securities, Current				85,500,000
Auction Rate Securities [Member]
Note 8 - Fair Value Measurements (Details) [Line Items]
Auction Rate Securities, Noncurrent				11,800,000
US Government Agencies Short-term Debt Securities [Member]
Note 8 - Fair Value Measurements (Details) [Line Items]
Available-for-sale Securities	87,884,000			85,521,000
Available-for-sale Securities, Gross Unrealized Loss	19,000			7,000
Government Backed Securities [Member]
Note 8 - Fair Value Measurements (Details) [Line Items]
Auction Rate Securities, Noncurrent	$ 11,700,000