Fair Value Measurements (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value - available for sale	$ 462,534	$ 479,323
Fixed maturities [Member]
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value - available for sale		425,191
U.S. Treasury securities and obligations of U.S. government agencies [Member]
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value - available for sale	606	9,098
Obligations of states, municipalities and political subdivisions [Member]
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value - available for sale	158,715	164,326
Corporate and other securities [Member]
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value - available for sale	93,664	71,631
Asset-backed securities [Member]
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value - available for sale	122,937	95,360
Residential mortgage-backed securities [Member]
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value - available for sale	86,612	84,776
Equity securities [Member]
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value - available for sale		54,132
Exchange traded funds [Member]
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value - available for sale		34,380
Nonredeemable preferred stock [Member]
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value - available for sale		19,752
Recurring
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value	517,599
Fair value - available for sale		479,323
Recurring | Level 1
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value	36,545
Fair value - available for sale		43,478
Recurring | Level 2
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value	481,054
Fair value - available for sale		435,845
Recurring | Level 3
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value	0
Fair value - available for sale		0
Recurring | Fixed maturities [Member]
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value - available for sale	462,534	425,191
Recurring | Fixed maturities [Member] | Level 1
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value - available for sale	606	9,098
Recurring | Fixed maturities [Member] | Level 2
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value - available for sale	461,928	416,093
Recurring | Fixed maturities [Member] | Level 3
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value - available for sale	0	0
Recurring | U.S. Treasury securities and obligations of U.S. government agencies [Member]
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value - available for sale	606	9,098
Recurring | U.S. Treasury securities and obligations of U.S. government agencies [Member] | Level 1
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value - available for sale	606	9,098
Recurring | U.S. Treasury securities and obligations of U.S. government agencies [Member] | Level 2
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value - available for sale	0	0
Recurring | U.S. Treasury securities and obligations of U.S. government agencies [Member] | Level 3
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value - available for sale	0	0
Recurring | Obligations of states, municipalities and political subdivisions [Member]
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value - available for sale	158,715	164,326
Recurring | Obligations of states, municipalities and political subdivisions [Member] | Level 1
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value - available for sale	0	0
Recurring | Obligations of states, municipalities and political subdivisions [Member] | Level 2
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value - available for sale	158,715	164,326
Recurring | Obligations of states, municipalities and political subdivisions [Member] | Level 3
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value - available for sale	0	0
Recurring | Corporate and other securities [Member]
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value - available for sale	93,664	71,631
Recurring | Corporate and other securities [Member] | Level 1
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value - available for sale	0	0
Recurring | Corporate and other securities [Member] | Level 2
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value - available for sale	93,664	71,631
Recurring | Corporate and other securities [Member] | Level 3
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value - available for sale	0	0
Recurring | Asset-backed securities [Member]
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value - available for sale	122,937	95,360
Recurring | Asset-backed securities [Member] | Level 1
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value - available for sale	0	0
Recurring | Asset-backed securities [Member] | Level 2
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value - available for sale	122,937	95,360
Recurring | Asset-backed securities [Member] | Level 3
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value - available for sale	0	0
Recurring | Residential mortgage-backed securities [Member]
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value - available for sale	86,612	84,776
Recurring | Residential mortgage-backed securities [Member] | Level 1
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value - available for sale	0	0
Recurring | Residential mortgage-backed securities [Member] | Level 2
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value - available for sale	86,612	84,776
Recurring | Residential mortgage-backed securities [Member] | Level 3
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value - available for sale	0	0
Recurring | Equity securities [Member]
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value	55,065
Fair value - available for sale		54,132
Recurring | Equity securities [Member] | Level 1
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value	35,939
Fair value - available for sale		34,380
Recurring | Equity securities [Member] | Level 2
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value	19,126
Fair value - available for sale		19,752
Recurring | Equity securities [Member] | Level 3
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value	0
Fair value - available for sale		0
Recurring | Exchange traded funds [Member]
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value	35,939
Fair value - available for sale		34,380
Recurring | Exchange traded funds [Member] | Level 1
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value	35,939
Fair value - available for sale		34,380
Recurring | Exchange traded funds [Member] | Level 2
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value	0
Fair value - available for sale		0
Recurring | Exchange traded funds [Member] | Level 3
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value	0
Fair value - available for sale		0
Recurring | Nonredeemable preferred stock [Member]
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value	19,126
Fair value - available for sale		19,752
Recurring | Nonredeemable preferred stock [Member] | Level 1
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value	0
Fair value - available for sale		0
Recurring | Nonredeemable preferred stock [Member] | Level 2
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value	19,126
Fair value - available for sale		19,752
Recurring | Nonredeemable preferred stock [Member] | Level 3
Fair Value of Investments Measured on Recurring Basis [Line Items]
Fair value	$ 0
Fair value - available for sale		$ 0