Balance Sheet Accounts (Schedule of Available-for-sale Investments by Contractual Maturity) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014
Amortized Cost
Due in 1 year or less	$ 24,697
Due in 1-2 years	7,553
Due in 2-5 years	3,016
Total investments in available for sale debt securities	35,266
Fair Value
Due in 1 year or less	24,803
Due in 1-2 years	7,568
Due in 2-5 years	3,016
Total investments in available for sale debt securities	$ 35,387

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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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.

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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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