Investments - Contractual Maturities of Investments (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013
Cost
Due in one year or less	$ 84,964
Due after one year through five years	16,728
Due after five years through ten years	13,718
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis	115,410
Fair Value
Due in one year or less	84,982
Due after one year through five years	16,343
Due after five years through ten years	13,194
Fair Value	$ 114,519

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 rolling twelve months following the latest balance sheet presented. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings (less 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 rolling twelve months following the latest balance sheet presented.

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Amount of available-for-sale debt securities at cost, net of adjustments, maturing in the sixth rolling twelve months through the tenth rolling twelve months following the latest balance sheet presented. 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 sixth rolling twelve months through the tenth rolling twelve months following the latest balance sheet presented.

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Amount of available-for-sale debt securities at cost, net of adjustments, maturing in the second rolling twelve months through the fifth rolling twelve months following the latest balance sheet presented. 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 second rolling twelve months through the fifth rolling twelve months following the latest balance sheet presented.

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

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