Investments Classified by Maturity Date (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Debt Maturities, within One Year, Amortized Cost Basis, Percent of Total	14.50%
Available-for-sale Securities, Debt Maturities, within One Year, Fair Value, Percent of Total	14.40%
Available-for-sale Securities, Debt Maturities, after One Through Five Years, Amortized Cost Basis, Percent of Total	48.80%
Available-for-sale Securities, Debt Maturities, after One Through Five Years, Fair Value, Percent of Total	48.50%
Available-for-sale Securities, Debt Maturities, after Five Through Ten Years, Amortized Cost Basis, Percent of Total	32.60%
Available-for-sale Securities, Debt Maturities, after Five Through Ten Years, Fair Value, Percent of Total	32.90%
Available-for-sale Securities, Debt Maturities, after Ten Years, Amortized Cost Basis, Percent of Total	4.10%
Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value, Percent of Total	4.20%
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Percent of Total	100.00%
Available-for-sale Securities, Debt Securities	$ 285,849	$ 273,024
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	41,156
Available-for-sale Securities, Debt Maturities, Next Twelve Months, Fair Value	41,236
Available-for-sale Securities, Debt Maturities, Year Two Through Five, Amortized Cost Basis	137,899
Available-for-sale Securities, Debt Maturities, Year Two Through Five, Fair Value	138,577
Available-for-sale Securities, Debt Maturities, Year Six Through Ten, Amortized Cost Basis	92,090
Available-for-sale Securities, Debt Maturities, Year Six Through Ten, Fair Value	94,157
Available-for-sale Securities, Debt Maturities, after Ten Years, Amortized Cost Basis	11,551
Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value	11,879
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis	282,696
Available-for-sale Securities, Debt Securities	$ 285,849	$ 273,024