Balance Sheet Accounts (Schedule of Available-for-sale Investments by Contractual Maturity) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013
Amortized Cost
Due in 1 year or less	$ 164,416
Total investments in available for sale debt securities	164,416
Fair Value
Due in 1 year or less	164,581
Total investments in available for sale debt securities	$ 164,581

Available-for-sale Securities, Debt Maturities, Fair Value Amount

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Amount of available-for-sale debt securities at cost, net of adjustments, which include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings (less any cumulative-effect adjustments, as defined) and fair value hedge accounting adjustments.

+ References

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Amount of available-for-sale debt securities at cost, net of adjustments, maturing in the next fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings (less any cumulative-effect adjustments, as defined) and fair value hedge accounting adjustments.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.2)

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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

-Name Accounting Standards Codification

-Topic 320

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