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, 2012
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Fiscal Year Maturity [Abstract]
Due in 1 year or less	$ 23,311
Due in 1-2 years	52,965
Due in 2-5 years	22,585
Due in more than 5 years	0
Total investments in available for sale debt securities	98,861
Available-for-sale Securities, Debt Maturities, Fair Value, Fiscal Year Maturity [Abstract]
Due in 1 year or less	23,357
Due in 1-2 years	52,994
Due in 2-5 years	22,568
Due in more than 5 years	0
Total investments in available for sale debt securities	$ 98,919

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

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Available-for-sale Securities, Debt Maturities, After Year Five, Fair Value

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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

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 20

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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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-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 20

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

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