Investments by Category and Level (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	$ 528,647	$ 452,714
US Government and Government Agencies and Authorities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	149,952	81,647
Foreign Government Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	2,061	2,075
US States and Political Subdivisions Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	169,112	155,905
Public Utility, Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	7,730	8,493
Corporate Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	164,536	146,758
Redeemable Preferred Stock [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	1,125	1,820
Fixed Maturities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	494,516	396,698
Mutual Fund [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities		26,343
Public Utility, Equities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	1,507	1,352
Common Stock
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	24,048	20,694
Nonredeemable Preferred Stock [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	2,843	2,417
Equity Securities
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	28,398	50,806
Other Long-term Investments
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	5,733	5,210
Level 1 [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	29,823	52,926
Level 1 [Member] | US Government and Government Agencies and Authorities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	0	0
Level 1 [Member] | Foreign Government Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	0	0
Level 1 [Member] | US States and Political Subdivisions Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	0	0
Level 1 [Member] | Public Utility, Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	0	0
Level 1 [Member] | Corporate Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	0	0
Level 1 [Member] | Redeemable Preferred Stock [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	1,125	1,820
Level 1 [Member] | Fixed Maturities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	1,125	1,820
Level 1 [Member] | Mutual Fund [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities		26,343
Level 1 [Member] | Public Utility, Equities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	1,507	1,352
Level 1 [Member] | Common Stock
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	24,048	20,694
Level 1 [Member] | Nonredeemable Preferred Stock [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	2,843	2,417
Level 1 [Member] | Equity Securities
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	28,398	50,806
Level 1 [Member] | Other Long-term Investments
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	300	300
Level 2
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	497,126	397,933
Level 2 | US Government and Government Agencies and Authorities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	149,952	81,647
Level 2 | Foreign Government Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	2,061	2,075
Level 2 | US States and Political Subdivisions Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	169,112	155,905
Level 2 | Public Utility, Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	7,730	8,493
Level 2 | Corporate Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	164,536	146,758
Level 2 | Redeemable Preferred Stock [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	0	0
Level 2 | Fixed Maturities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	493,391	394,878
Level 2 | Mutual Fund [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities		0
Level 2 | Public Utility, Equities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	0	0
Level 2 | Common Stock
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	0	0
Level 2 | Nonredeemable Preferred Stock [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	0	0
Level 2 | Equity Securities
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	0	0
Level 2 | Other Long-term Investments
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	3,735	3,055
Fair Value, Inputs, Level 3
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	1,698	1,855
Fair Value, Inputs, Level 3 | US Government and Government Agencies and Authorities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	0	0
Fair Value, Inputs, Level 3 | Foreign Government Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	0	0
Fair Value, Inputs, Level 3 | US States and Political Subdivisions Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	0	0
Fair Value, Inputs, Level 3 | Public Utility, Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	0	0
Fair Value, Inputs, Level 3 | Corporate Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	0	0
Fair Value, Inputs, Level 3 | Redeemable Preferred Stock [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	0	0
Fair Value, Inputs, Level 3 | Fixed Maturities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	0	0
Fair Value, Inputs, Level 3 | Mutual Fund [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities		0
Fair Value, Inputs, Level 3 | Public Utility, Equities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	0	0
Fair Value, Inputs, Level 3 | Common Stock
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	0	0
Fair Value, Inputs, Level 3 | Nonredeemable Preferred Stock [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	0	0
Fair Value, Inputs, Level 3 | Equity Securities
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	0	0
Fair Value, Inputs, Level 3 | Other Long-term Investments
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	$ 1,698	$ 1,855