Basis of Presentation and Summary of Significant Accounting Policies (Schedule of Available-for-sale Investments by Contractual Maturity) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Fiscal Year Maturity [Abstract]
Due in 1 year or less	$ 42,994
Due in 1-2 years	33,516
Due in 2-5 years	33,568
Total investments in available for sale debt securities	110,078
Available-for-sale Securities, Debt Maturities, Fair Value, Fiscal Year Maturity [Abstract]
Due in 1 year or less	43,034
Due in 1-2 years	33,540
Due in 2-5 years	33,236
Total investments in available for sale debt securities	$ 109,810

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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

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-Subparagraph (SX 210.5-02.2)

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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

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-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.

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