Long-Term Investments (Details) (USD $)	3 Months Ended	12 Months Ended
Sep. 30, 2012	Sep. 30, 2011	Jun. 30, 2012
Schedule of Investments [Line Items]
Fair value inputs, discount rate	0.36%
Fair value inputs, time period until redemption	3 years
Fair value investment, increase or decrease in rate of return	1.00%
Fair value investment, increase or decrease in term	1 year
Auction-rate securities, unrealized gains (losses), period impact	$ 0	$ 156,000
Auction Rate Securities [Member]
Schedule of Investments [Line Items]
Auction-rate securities, net of unrealized losses	2,923,000		2,923,000
Auction-rate securities, unrealized gains (losses), period impact	0	156,000
Auction-rate securities, unrealized holding gains (losses), gross	(127,000)		(127,000)
Auction-rate securities, unrealized holding gains (losses), net of taxes	(76,000)		(76,000)
Auction rate securities, redeemed at par	$ 0	$ 1,675,000
Minimum [Member]
Schedule of Investments [Line Items]
Fair value inputs, estimated rate of return	1.00%
Fair value, change in investment portfolio	1.00%
Maximum [Member]
Schedule of Investments [Line Items]
Fair value inputs, estimated rate of return	3.00%
Fair value, change in investment portfolio	3.00%

Fair Value, Change in Investment, Portfolio

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Fair Value, Estimated Rate of Return

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Fair Value, Time Period Until Redemption

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Investments in debt and equity securities which are categorized neither as held-to-maturity nor trading and which are intended to be sold or mature more than one year from the balance sheet date or operating cycle, if longer. Such securities are reported at fair value; unrealized gains (losses) related to Available-for-sale Securities are excluded from earnings and reported in a separate component of shareholders' equity (other comprehensive income), unless the Available-for-sale security is designated as a hedge or is determined to have had an other than temporary decline in fair value below its amortized cost basis. All or a portion of the unrealized holding gain (loss) of an Available-for-sale security that is designated as being hedged in a fair value hedge is recognized in earnings during the period of the hedge, as are other than temporary declines in fair value below the cost basis for investments in equity securities and debt securities that an entity intends to sell or it is more likely than not that it will be required to sell before the recovery of its amortized cost basis. Other than temporary declines in fair value below the cost basis for debt securities categorized as Available-for-sale that an entity does not intend to sell and for which it is not more likely than not that the entity will be required to sell before the recovery of its amortized cost basis are bifurcated into credit losses and losses related to all other factors. Other than temporary declines in fair value below cost basis related to credit losses are recognized in earnings, and losses related to all other factors are recognized in other comprehensive income.

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The aggregate value of securities held, which were categorized neither as trading nor held-to-maturity, for which the interest rate reset through an auction process, that failed to be liquidated through auction, and which were sold at par value during the period.

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Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

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Amount of gain (loss) recognized in other comprehensive income, arising from assets measured at fair value on a recurring basis using unobservable inputs (level 3).

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Net of tax amount of the appreciation (loss) in value of unsold available-for-sale securities attributable to the parent entity. Excludes amounts related to other than temporary impairment (OTTI) losses.

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Before tax and reclassification adjustments amount of unrealized holding gain (loss) on available-for-sale securities.

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