Investments (Details 1) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012
Amortized cost and estimated fair value of fixed maturity securities by contractual maturity
Due in one year or less, Amortized cost	$ 42,252
Due after one year through five years, Amortized cost	80,828
Due after five years through ten years, Amortized cost	178,448
Due after ten years, Amortized cost	77,441
Mortgage and asset-backed securities, Amortized cost	342,498
Amortized cost, Total	721,467
Due in one year or less, Estimated fair value	43,073
Due after one year through five years, Estimated fair value	87,916
Due after five years through ten years, Estimated fair value	198,782
Due after ten years, Estimated fair value	97,428
Mortgage and asset-backed securities, Estimated fair value	364,562
Estimated fair value, Total	$ 791,761

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Amount of available-for-sale debt securities at cost, net of adjustments, maturing in the sixth fiscal year through the tenth 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 cost, net of adjustments, maturing in the second fiscal year through the fifth 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 cost, net of adjustments, maturing after the tenth 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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