Balance Sheet Accounts (Schedule of Available-for-sale Investments by Contractual Maturity) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014
Amortized Cost
Due in 1 year or less	$ 23,312
Due in 1-2 years	6,024
Due in 2-5 years	1,002
Total investments in available for sale debt securities	30,338
Fair Value
Due in 1 year or less	23,363
Due in 1-2 years	6,027
Due in 2-5 years	1,005
Total investments in available for sale debt securities	$ 30,395

Available-for-sale Securities, Debt Maturities, After Year One and Before Two, Amortized Cost Basis

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Available-for-sale Securities, Debt Maturities, After Year One and Before Two, Fair Value

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Available-for-sale Securities, Debt Maturities, After Year Two Through Five, Amortized Cost Basis

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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.

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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.

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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.

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