Investments - Schedule of Available-for-sale Securities Reconciliation (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Schedule of Available-for-sale Securities
Other investments, cost	$ 776,054	$ 527,183
Gross unrealized gains	15,162	7,598
Gross unrealized loss	2,635	6,134
Total investments	788,581	528,647
U.S. Government and Agency Securities
Schedule of Available-for-sale Securities
Cost or adjusted/amortized cost	204,132	151,656
Gross unrealized gains	618	189
Gross unrealized loss	1,294	1,893
Fair Value	203,456	149,952
Foreign Government
Schedule of Available-for-sale Securities
Cost or adjusted/amortized cost	2,025	2,031
Gross unrealized gains	32	30
Gross unrealized loss	0	0
Fair Value	2,057	2,061
States, Municipalities and Political Subdivisions
Schedule of Available-for-sale Securities
Cost or adjusted/amortized cost	194,327	170,636
Gross unrealized gains	2,249	1,027
Gross unrealized loss	429	2,551
Fair Value	196,147	169,112
Public Utilities
Schedule of Available-for-sale Securities
Cost or adjusted/amortized cost	19,601	7,687
Gross unrealized gains	205	116
Gross unrealized loss	51	73
Fair Value	19,755	7,730
Corporate Securities
Schedule of Available-for-sale Securities
Cost or adjusted/amortized cost	277,481	164,424
Gross unrealized gains	2,692	1,238
Gross unrealized loss	580	1,126
Fair Value	279,593	164,536
Asset-backed Securities
Schedule of Available-for-sale Securities
Cost or adjusted/amortized cost	16,711
Gross unrealized gains	11
Gross unrealized loss	8
Fair Value	16,714
Redeemable Preferred Stocks
Schedule of Available-for-sale Securities
Cost or adjusted/amortized cost	1,097	1,182
Gross unrealized gains	29	5
Gross unrealized loss	63	62
Fair Value	1,063	1,125
Fixed Maturities
Schedule of Available-for-sale Securities
Cost or adjusted/amortized cost	715,374	497,616
Gross unrealized gains	5,836	2,605
Gross unrealized loss	2,425	5,705
Fair Value	718,785	494,516
Mutual Fund
Schedule of Available-for-sale Securities
Cost or adjusted/amortized cost	28,949
Gross unrealized gains	858
Gross unrealized loss	0
Fair Value	29,807
Public Utilities
Schedule of Available-for-sale Securities
Cost or adjusted/amortized cost	1,342	1,343
Gross unrealized gains	300	164
Gross unrealized loss	0	0
Fair Value	1,642	1,507
Common Stock
Schedule of Available-for-sale Securities
Cost or adjusted/amortized cost	19,804	19,815
Gross unrealized gains	7,790	4,552
Gross unrealized loss	149	319
Fair Value	27,445	24,048
Nonredeemable Preferred Stocks
Schedule of Available-for-sale Securities
Cost or adjusted/amortized cost	2,750	2,916
Gross unrealized gains	56	10
Gross unrealized loss	61	83
Fair Value	2,745	2,843
Equity Securities
Schedule of Available-for-sale Securities
Cost or adjusted/amortized cost	52,845	24,074
Gross unrealized gains	9,004	4,726
Gross unrealized loss	210	402
Fair Value	61,639	28,398
Other Long-term Investments
Schedule of Available-for-sale Securities
Other investments, cost	7,835	5,493
Gross unrealized gains	322	267
Gross unrealized loss	0	27
Other Long-term Investments	$ 8,157	$ 5,733

This item represents the cost of debt 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.

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