Investments - Summary of Cost or Amortized Cost, Gross Unrealized Gains and Losses, and Estimated Fair Value Available-for-Sale Securities (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	$ 129,680	$ 110,738
Equity securities, Cost or Amortized Cost	22,174	17,248
Total available-for-sale securities, Cost or Amortized Cost	151,854	127,986
Debt securities	133,113	112,151
Total available-for-sale securities, gross unrealized gain	4,747	2,862
Total available-for-sale securities, gross unrealized loss	(616)	(1,048)
Equity securities	22,872	17,649
Total available-for-sale securities	155,985	129,800
Fixed-Maturity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	129,680	110,738
Gross Unrealized Gain	3,634	1,942
Gross Unrealized Loss	(201)	(529)
Debt securities	133,113	112,151
Fixed-Maturity Securities [Member] | U.S. Treasury and U.S. Government Agencies [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	4,351	4,549
Gross Unrealized Gain	103	37
Gross Unrealized Loss	(1)	(22)
Debt securities	4,453	4,564
Fixed-Maturity Securities [Member] | Corporate Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	30,062	25,139
Gross Unrealized Gain	781	484
Gross Unrealized Loss	(71)	(219)
Debt securities	30,772	25,404
Fixed-Maturity Securities [Member] | Commercial Mortgage-Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	10,867	10,929
Gross Unrealized Gain	470	499
Gross Unrealized Loss	(59)	(96)
Debt securities	11,278	11,332
Fixed-Maturity Securities [Member] | State, Municipalities, and Political Subdivisions [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	80,877	69,715
Gross Unrealized Gain	2,234	917
Gross Unrealized Loss	(66)	(181)
Debt securities	83,045	70,451
Fixed-Maturity Securities [Member] | Redeemable Preferred Stock [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	3,523	406
Gross Unrealized Gain	46	5
Gross Unrealized Loss	(4)	(11)
Debt securities	3,565	400
Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Equity securities, Cost or Amortized Cost	22,174	17,248
Equity securities, gross unrealized gain	1,113	920
Equity securities, gross unrealized loss	(415)	(519)
Equity securities	$ 22,872	$ 17,649