Investments - Summary of Amortized Cost, Gross Unrealized Gains and Losses, and Estimated Fair Value of Available-for-Sale Securities (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]
Fixed-maturity securities, Cost or Amortized Cost	$ 96,163	$ 110,738
Total available-for-sale securities, Gross Unrealized Gain	3,148	2,862
Equity securities, Cost or Amortized Cost	45,387	17,248
Total Available-for-sale securities, Gross Unrealized Loss	(2,064)	(1,048)
Total available-for-sale securities, Cost or Amortized Cost	141,550	127,986
Total available-for-sale securities, Estimated Fair Value	97,084	112,151
Equity securities, Estimated Fair Value	45,550	17,649
Total available-for-sale securities, Estimated Fair Value	142,634	129,800
Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Total available-for-sale securities, Gross Unrealized Gain	1,694	920
Equity securities, Cost or Amortized Cost	45,387	17,248
Total Available-for-sale securities, Gross Unrealized Loss	(1,531)	(519)
Equity securities, Estimated Fair Value	45,550	17,649
Fixed-Maturity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed-maturity securities, Cost or Amortized Cost	96,163	110,738
Total available-for-sale securities, Gross Unrealized Gain	1,454	1,942
Total Available-for-sale securities, Gross Unrealized Loss	(533)	(529)
Total available-for-sale securities, Estimated Fair Value	97,084	112,151
Fixed-Maturity Securities [Member] | U.S. Treasury and U.S. Government Agencies [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed-maturity securities, Cost or Amortized Cost	3,747	4,549
Total available-for-sale securities, Gross Unrealized Gain	9	37
Total Available-for-sale securities, Gross Unrealized Loss	(8)	(22)
Total available-for-sale securities, Estimated Fair Value	3,748	4,564
Fixed-Maturity Securities [Member] | Corporate Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed-maturity securities, Cost or Amortized Cost	24,342	25,139
Total available-for-sale securities, Gross Unrealized Gain	57	484
Total Available-for-sale securities, Gross Unrealized Loss	(430)	(219)
Total available-for-sale securities, Estimated Fair Value	23,969	25,404
Fixed-Maturity Securities [Member] | Mortgage-Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed-maturity securities, Cost or Amortized Cost	2,138	10,929
Total available-for-sale securities, Gross Unrealized Gain	4	499
Total Available-for-sale securities, Gross Unrealized Loss	(3)	(96)
Total available-for-sale securities, Estimated Fair Value	2,139	11,332
Fixed-Maturity Securities [Member] | State, Municipalities, and Political Subdivisions [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed-maturity securities, Cost or Amortized Cost	56,336	69,715
Total available-for-sale securities, Gross Unrealized Gain	1,205	917
Total Available-for-sale securities, Gross Unrealized Loss	(38)	(181)
Total available-for-sale securities, Estimated Fair Value	57,503	70,451
Fixed-Maturity Securities [Member] | Redeemable Preferred Stock [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed-maturity securities, Cost or Amortized Cost	9,433	406
Total available-for-sale securities, Gross Unrealized Gain	178	5
Total Available-for-sale securities, Gross Unrealized Loss	(54)	(11)
Total available-for-sale securities, Estimated Fair Value	9,557	400
Fixed-Maturity Securities [Member] | Other [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed-maturity securities, Cost or Amortized Cost	167
Total available-for-sale securities, Gross Unrealized Gain	1
Total available-for-sale securities, Estimated Fair Value	$ 168