Maturities of Investments (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013
Schedule Of Investments [Line Items]
Less than 1 year	$ 23,114
Due in 1 to 2 years
Due in 2 to 5 years	2,005
Due after 5 years	1,800
Total	$ 26,919

Available for Sale Securities, Debt Maturities, after One Through Two Years, Fair Value

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- Definition

Available for Sale Securities, Debt Maturities, after Two Through Five Years, Fair Value

+ References

No definition available.

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- Definition

Amount of available-for-sale debt securities at fair value maturing in the sixth fiscal year through the tenth fiscal year following the latest fiscal year.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

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Amount of available-for-sale debt securities at fair value maturing in the next fiscal year following the latest fiscal year.

+ References

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

-Publisher FASB

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- Definition

Amount of debt securities categorized neither as held-to-maturity nor trading.

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-Name Accounting Standards Codification

-Topic 320

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