Investments, Available-for-sale Investments (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Total available-for-sale investments [Abstract]
Amortized cost	$ 514,237	$ 468,171
Gross unrealized holding gains	2,882	13,627
Gross unrealized holding losses	(6,868)	(2,475)
Estimated fair value	510,251	479,323
Fixed Maturities [Member]
Total available-for-sale investments [Abstract]
Amortized cost		422,255
Gross unrealized holding gains		5,180
Gross unrealized holding losses		(2,244)
Estimated fair value		425,191
U.S. Treasury Securities and Obligations of U.S. Government Agencies [Member]
Total available-for-sale investments [Abstract]
Amortized cost	610	9,108
Gross unrealized holding gains	2	4
Gross unrealized holding losses	(1)	(14)
Estimated fair value	611	9,098
Obligations of States, Municipalities and Political Subdivisions [Member]
Total available-for-sale investments [Abstract]
Amortized cost	153,884	161,012
Gross unrealized holding gains	2,010	3,726
Gross unrealized holding losses	(1,294)	(412)
Estimated fair value	154,600	164,326
Corporate and Other Securities [Member]
Total available-for-sale investments [Abstract]
Amortized cost	97,889	71,224
Gross unrealized holding gains	264	579
Gross unrealized holding losses	(1,401)	(172)
Estimated fair value	96,752	71,631
Asset-backed Securities [Member]
Total available-for-sale investments [Abstract]
Amortized cost	151,137	95,223
Gross unrealized holding gains	252	405
Gross unrealized holding losses	(1,522)	(268)
Estimated fair value	149,867	95,360
Residential Mortgage-backed Securities [Member]
Total available-for-sale investments [Abstract]
Amortized cost	110,717	85,688
Gross unrealized holding gains	354	466
Gross unrealized holding losses	(2,650)	(1,378)
Estimated fair value	$ 108,421	84,776
Equity Securities [Member]
Total available-for-sale investments [Abstract]
Amortized cost		45,916
Gross unrealized holding gains		8,447
Gross unrealized holding losses		(231)
Estimated fair value		54,132
Exchange Traded Fund [Member]
Total available-for-sale investments [Abstract]
Amortized cost		26,041
Gross unrealized holding gains		8,339
Gross unrealized holding losses		0
Estimated fair value		34,380
Nonredeemable Preferred Stock [Member]
Total available-for-sale investments [Abstract]
Amortized cost		19,875
Gross unrealized holding gains		108
Gross unrealized holding losses		(231)
Estimated fair value		$ 19,752

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

No definition available.

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- Definition

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

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- Definition

Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

No definition available.

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- Definition

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

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- References

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