Investments Classified by Maturity Date (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Jun. 30, 2012
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Debt Maturities, within One Year, Amortized Cost Basis, Percent of Total	8.30%
Available-for-sale Securities, Debt Maturities, within One Year, Fair Value, Percent of Total	8.40%
Available-for-sale Securities, Debt Maturities, after One Through Five Years, Amortized Cost Basis, Percent of Total	52.80%
Available-for-sale Securities, Debt Maturities, after One Through Five Years, Fair Value, Percent of Total	52.70%
Available-for-sale Securities, Debt Maturities, after Five Through Ten Years, Amortized Cost Basis, Percent of Total	25.30%
Available-for-sale Securities, Debt Maturities, after Five Through Ten Years, Fair Value, Percent of Total	25.10%
Available-for-sale Securities, Debt Maturities, after Ten Years, Amortized Cost Basis, Percent of Total	13.60%
Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value, Percent of Total	13.80%
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Percent of Total	100.00%
Available-for-sale Securities, Fair Value Disclosure	$ 241,963	$ 152,180
Available-for-sale Securities, Fair Value Disclosure, Percent of Total	100.00%
Fixed Maturities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Debt Maturities, Next Twelve Months, Amortized Cost Basis	19,292
Available-for-sale Securities, Debt Maturities, Next Twelve Months, Fair Value	19,319
Available-for-sale Securities, Debt Maturities, Year Two Through Five, Amortized Cost Basis	122,489
Available-for-sale Securities, Debt Maturities, Year Two Through Five, Fair Value	122,040
Available-for-sale Securities, Debt Maturities, Year Six Through Ten, Amortized Cost Basis	58,574
Available-for-sale Securities, Debt Maturities, Year Six Through Ten, Fair Value	58,112
Available-for-sale Securities, Debt Maturities, after Ten Years, Amortized Cost Basis	31,615
Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value	32,022
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis	231,970
Available-for-sale Securities, Fair Value Disclosure	$ 231,493	$ 149,157