Fair Value - Presentation of Fair-Value Measurements for Each Major Category of Assets Measured on Recurring Basis (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2013 Fair Value Measurements Using [Member]	Dec. 31, 2012 Fair Value Measurements Using [Member]	Sep. 30, 2013 Fair Value Measurements Using [Member] Debt Securities [Member]	Dec. 31, 2012 Fair Value Measurements Using [Member] Debt Securities [Member]	Sep. 30, 2013 Fair Value Measurements Using [Member] Debt Securities [Member] U.S. Government and Agencies [Member]	Dec. 31, 2012 Fair Value Measurements Using [Member] Debt Securities [Member] U.S. Government and Agencies [Member]	Sep. 30, 2013 Fair Value Measurements Using [Member] Debt Securities [Member] State [Member]	Dec. 31, 2012 Fair Value Measurements Using [Member] Debt Securities [Member] State [Member]	Sep. 30, 2013 Fair Value Measurements Using [Member] Debt Securities [Member] Political Subdivisions [Member]	Dec. 31, 2012 Fair Value Measurements Using [Member] Debt Securities [Member] Political Subdivisions [Member]	Sep. 30, 2013 Fair Value Measurements Using [Member] Debt Securities [Member] Revenue and Assessment [Member]	Dec. 31, 2012 Fair Value Measurements Using [Member] Debt Securities [Member] Revenue and Assessment [Member]	Sep. 30, 2013 Fair Value Measurements Using [Member] Debt Securities [Member] Corporate Bonds [Member]	Dec. 31, 2012 Fair Value Measurements Using [Member] Debt Securities [Member] Corporate Bonds [Member]	Sep. 30, 2013 Fair Value Measurements Using [Member] Debt Securities [Member] Agency Backed [Member]	Dec. 31, 2012 Fair Value Measurements Using [Member] Debt Securities [Member] Agency Backed [Member]	Sep. 30, 2013 Fair Value Measurements Using [Member] Debt Securities [Member] Non-Agency Backed - Residential [Member]	Dec. 31, 2012 Fair Value Measurements Using [Member] Debt Securities [Member] Non-Agency Backed - Residential [Member]	Sep. 30, 2013 Fair Value Measurements Using [Member] Debt Securities [Member] Non-Agency Backed - Commercial [Member]	Dec. 31, 2012 Fair Value Measurements Using [Member] Debt Securities [Member] Non-Agency Backed - Commercial [Member]	Sep. 30, 2013 Fair Value Measurements Using [Member] Debt Securities [Member] Redeemable Preferred Stocks [Member]	Dec. 31, 2012 Fair Value Measurements Using [Member] Debt Securities [Member] Redeemable Preferred Stocks [Member]	Sep. 30, 2013 Fair Value Measurements Using [Member] Equity Securities [Member]	Dec. 31, 2012 Fair Value Measurements Using [Member] Equity Securities [Member]	Sep. 30, 2013 Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Fair Value Measurements Using [Member]	Dec. 31, 2012 Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Fair Value Measurements Using [Member]	Sep. 30, 2013 Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Fair Value Measurements Using [Member] Debt Securities [Member]	Dec. 31, 2012 Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Fair Value Measurements Using [Member] Debt Securities [Member]	Sep. 30, 2013 Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Fair Value Measurements Using [Member] Debt Securities [Member] U.S. Government and Agencies [Member]	Dec. 31, 2012 Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Fair Value Measurements Using [Member] Debt Securities [Member] U.S. Government and Agencies [Member]	Sep. 30, 2013 Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Fair Value Measurements Using [Member] Debt Securities [Member] Redeemable Preferred Stocks [Member]	Dec. 31, 2012 Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Fair Value Measurements Using [Member] Debt Securities [Member] Redeemable Preferred Stocks [Member]	Sep. 30, 2013 Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Fair Value Measurements Using [Member] Equity Securities [Member]	Dec. 31, 2012 Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Fair Value Measurements Using [Member] Equity Securities [Member]	Sep. 30, 2013 Significant Other Observable Inputs (Level 2) [Member] Fair Value Measurements Using [Member]	Dec. 31, 2012 Significant Other Observable Inputs (Level 2) [Member] Fair Value Measurements Using [Member]	Sep. 30, 2013 Significant Other Observable Inputs (Level 2) [Member] Fair Value Measurements Using [Member] Debt Securities [Member]	Dec. 31, 2012 Significant Other Observable Inputs (Level 2) [Member] Fair Value Measurements Using [Member] Debt Securities [Member]	Sep. 30, 2013 Significant Other Observable Inputs (Level 2) [Member] Fair Value Measurements Using [Member] Debt Securities [Member] State [Member]	Dec. 31, 2012 Significant Other Observable Inputs (Level 2) [Member] Fair Value Measurements Using [Member] Debt Securities [Member] State [Member]	Sep. 30, 2013 Significant Other Observable Inputs (Level 2) [Member] Fair Value Measurements Using [Member] Debt Securities [Member] Political Subdivisions [Member]	Dec. 31, 2012 Significant Other Observable Inputs (Level 2) [Member] Fair Value Measurements Using [Member] Debt Securities [Member] Political Subdivisions [Member]	Sep. 30, 2013 Significant Other Observable Inputs (Level 2) [Member] Fair Value Measurements Using [Member] Debt Securities [Member] Revenue and Assessment [Member]	Dec. 31, 2012 Significant Other Observable Inputs (Level 2) [Member] Fair Value Measurements Using [Member] Debt Securities [Member] Revenue and Assessment [Member]	Sep. 30, 2013 Significant Other Observable Inputs (Level 2) [Member] Fair Value Measurements Using [Member] Debt Securities [Member] Corporate Bonds [Member]	Dec. 31, 2012 Significant Other Observable Inputs (Level 2) [Member] Fair Value Measurements Using [Member] Debt Securities [Member] Corporate Bonds [Member]	Sep. 30, 2013 Significant Other Observable Inputs (Level 2) [Member] Fair Value Measurements Using [Member] Debt Securities [Member] Agency Backed [Member]	Dec. 31, 2012 Significant Other Observable Inputs (Level 2) [Member] Fair Value Measurements Using [Member] Debt Securities [Member] Agency Backed [Member]	Sep. 30, 2013 Significant Other Observable Inputs (Level 2) [Member] Fair Value Measurements Using [Member] Debt Securities [Member] Non-Agency Backed - Residential [Member]	Dec. 31, 2012 Significant Other Observable Inputs (Level 2) [Member] Fair Value Measurements Using [Member] Debt Securities [Member] Non-Agency Backed - Residential [Member]	Sep. 30, 2013 Significant Other Observable Inputs (Level 2) [Member] Fair Value Measurements Using [Member] Debt Securities [Member] Non-Agency Backed - Commercial [Member]	Dec. 31, 2012 Significant Other Observable Inputs (Level 2) [Member] Fair Value Measurements Using [Member] Debt Securities [Member] Non-Agency Backed - Commercial [Member]	Dec. 31, 2012 Significant Unobservable Inputs (Level 3) [Member]	Sep. 30, 2012 Significant Unobservable Inputs (Level 3) [Member]	Dec. 31, 2011 Significant Unobservable Inputs (Level 3) [Member]	Sep. 30, 2013 Significant Unobservable Inputs (Level 3) [Member] Fair Value Measurements Using [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mutual fund, available-for-sale																									$ 10,690	$ 8,333									$ 10,690	$ 8,333
Total fixed maturities, available-for-sale	135,428	139,046	135,428	139,046	124,738	130,713	11,596	12,110	724	4,111	1,668	790	16,072	17,996	75,693	71,537	6,242	11,870	6,383	5,472	4,801	5,109	1,559	1,718			23,845	22,161	13,155	13,828	11,596	12,110	1,559	1,718			111,583	116,885	111,583	116,885	724	4,111	1,668	790	16,072	17,996	75,693	71,537	6,242	11,870	6,383	5,472	4,801	5,109	0	0	0
Limited partnership interests	2,444		2,444																																																							2,444
Cash and cash equivalents			65,506	59,104																							65,506	59,104
Total			$ 203,378	$ 198,150																							$ 89,351	$ 81,265									$ 111,583	$ 116,885																				$ 2,444