Supplemental Information Concerning Property-Casualty Insurance Operations (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Schedule of Supplemental Information Concerning Property-Casualty Insurance Operations
Deferred Acquisition Costs	$ 26,182	$ 24,421	$ 22,142
Net Reserves for Unpaid Claims and Claim Adjustment Expenses	539,596	506,934	453,051
Net Unearned Premium	116,275	112,349	104,601
Net Earned Premium	253,866	232,879	200,733
Net Investment Income	30,198	31,338	32,138
Claims and Claim Adjustment Expenses Incurred Related to Current Year	162,660	155,998	119,939
Claims and Claim Adjustment Expenses Incurred Related to Prior Year	9,038	13,369	356
Amortization of Deferred Acquisition Costs	58,579	52,080	43,044
Other Operating Expenses	52,896	46,362	48,102
Net Premiums Written	255,360	240,618	223,240
E & S [Member]
Schedule of Supplemental Information Concerning Property-Casualty Insurance Operations
Deferred Acquisition Costs	16,074	12,830	11,807
Net Reserves for Unpaid Claims and Claim Adjustment Expenses	312,854	301,779	300,908
Net Unearned Premium	74,955	62,536	56,230
Net Earned Premium	138,464	119,225	102,907
Net Investment Income	17,615	18,572	21,331
Claims and Claim Adjustment Expenses Incurred Related to Current Year	84,250	70,741	60,516
Claims and Claim Adjustment Expenses Incurred Related to Prior Year	(1,780)	(10,209)	(2,397)
Amortization of Deferred Acquisition Costs	29,345	25,439	21,758
Net Premiums Written	148,297	125,107	114,223
ART [Member]
Schedule of Supplemental Information Concerning Property-Casualty Insurance Operations
Deferred Acquisition Costs	5,114	6,664	7,163
Net Reserves for Unpaid Claims and Claim Adjustment Expenses	92,290	92,683	69,884
Net Unearned Premium	18,496	25,747	29,248
Net Earned Premium	56,466	60,667	53,752
Net Investment Income	5,173	5,681	4,891
Claims and Claim Adjustment Expenses Incurred Related to Current Year	44,450	45,010	31,997
Claims and Claim Adjustment Expenses Incurred Related to Prior Year	2,946	12,120	2,666
Amortization of Deferred Acquisition Costs	15,918	17,761	13,809
Net Premiums Written	49,357	57,329	62,366
Reinsurance [Member]
Schedule of Supplemental Information Concerning Property-Casualty Insurance Operations
Deferred Acquisition Costs	4,994	4,927	3,172
Net Reserves for Unpaid Claims and Claim Adjustment Expenses	124,618	102,887	72,506
Net Unearned Premium	22,824	24,066	19,123
Net Earned Premium	58,936	52,988	44,081
Net Investment Income	6,849	6,358	5,231
Claims and Claim Adjustment Expenses Incurred Related to Current Year	33,967	40,268	27,432
Claims and Claim Adjustment Expenses Incurred Related to Prior Year	8,096	9,437	1,448
Amortization of Deferred Acquisition Costs	13,316	8,880	7,477
Net Premiums Written	57,706	58,183	46,658
Other Run-off [Member]
Schedule of Supplemental Information Concerning Property-Casualty Insurance Operations
Net Reserves for Unpaid Claims and Claim Adjustment Expenses	9,834	9,585	9,753
Net Earned Premium		(1)	(7)
Net Investment Income	561	727	685
Claims and Claim Adjustment Expenses Incurred Related to Current Year	(7)	(21)	(6)
Claims and Claim Adjustment Expenses Incurred Related to Prior Year	(224)	2,021	(1,361)
Net Premiums Written		$ (1)	$ (7)