Investments Realized Gain (Loss) on Investments (Details)	12 Months Ended
	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Gain (Loss) on Investments [Line Items]
Realized gains and losses on securities that are not going to be held before FV recovers	$ 30,000
Realized gains and losses on securities previously impaired		$ 256,000	$ 35,000
Proceeds from Sale of Available-for-sale Securities, Fixed Maturities	1,077,000	20,638,000	0
Proceeds from Sale of Available-for-sale Securities, Equity	1,940,000	5,100,000	43,163,000
Gain (Loss) on Sale of Properties	1,110,000	0	0
Gain (Loss) on Investments, Excluding Other than Temporary Impairments	(725,000)	(2,327,000)	74,000
Realized loss on Other than Temporary Impairments	(207,000)	(4,312,000)	(5,385,000)
Realized investment gains, net	518,000	(1,985,000)	(5,459,000)
Proceeds from Sale of Property, Plant, and Equipment	41,000	59,000	$ 0
Available-for-sale Securities [Member]
Gain (Loss) on Investments [Line Items]
Number of Debt Securities Sold			0
Debt Securities [Member]
Gain (Loss) on Investments [Line Items]
Proceeds from Sale of Available-for-sale Securities, Fixed Maturities		20,638,000
Available-for-sale Securities, Gross Realized Gains	19,000	1,487,000	$ 0
Available-for-sale Securities, Gross Realized Losses	(16,000)	0	0
Gain (Loss) on Sale, Calls and Maturities of Fixed Maturities	(506,000)	2,024,000	(111,000)
Other Than Temporary Impairment Losses on Debt and Equity Securities	$ 0	$ (3,970,000)	$ (2,998,000)
Equity Securities [Member]
Gain (Loss) on Investments [Line Items]
Number of Equity Securities Sold	1	5	6
Available-for-sale Securities, Gross Realized Gains	$ 0	$ 291,000	$ 634,000
Available-for-sale Securities, Gross Realized Losses	(30,000)	(35,000)	(599,000)
Gain (Loss) on Sale of Equity Securities	121,000	303,000	37,000
Other Than Temporary Impairment Losses on Debt and Equity Securities	$ (207,000)	$ (342,000)	$ (2,387,000)
Held-to-maturity Securities [Member]
Gain (Loss) on Investments [Line Items]
Number of Debt Securities Sold	0	0	0
SPLIC subsidiary of CICA [Domain]
Gain (Loss) on Investments [Line Items]
Proceeds from Sale of Property, Plant, and Equipment	$ 3,250,000
SPLIC subsidiary of CICA [Domain] | Available-for-sale Securities [Member]
Gain (Loss) on Investments [Line Items]
Number of Debt Securities Sold	1	11
SPFIC subsidiary of SPLIC [Domain] | Available-for-sale Securities [Member]
Gain (Loss) on Investments [Line Items]
Number of Debt Securities Sold	3