Investments - Schedule of Maturities (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013
Investments, Debt and Equity Securities [Abstract]
Less than 1 year, Cost	$ 9,205
Mature in 1 - 2 years, Cost	19,843
Mature in 3 - 5 years, Cost	1,575
Mature after 5 years, Cost	962
Cost, Total	31,585
Less than 1 year, Fair Value	9,217
Mature in 1 - 2 years, Fair Value	20,040
Mature in 3 - 5 years, Fair Value	1,649
Mature after 5 years, Fair Value	1,098
Fair Value, Total	$ 32,004

Available-for-sale securities, debt maturities, after five years, amortized cost.

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Available-for-sale securities, debt maturities, after five years, fair value.

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Available-for-sale securities, debt maturities, one to two years, amortized cost.

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Available-for-sale securities, debt maturities, one to two years, fair value.

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Available-for-sale securities, debt maturities, three to five years, amortized cost.

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Available-for-sale securities, debt maturities, three to five years, fair value.

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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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Amount of debt securities categorized neither as held-to-maturity nor trading.

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