Variable Interest Entity (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012	Jun. 30, 2012	Dec. 31, 2011
Assets and Liabilities of the VIE as consolidated in the Consolidated Balance Sheets
Cash and cash equivalents	$ 18,567	$ 20,224	$ 35,195	$ 43,481
Accrued investment income	1,693	6,387
Premiums receivable	29,249	32,559
Ceded unearned premium	35,200	29,821
Reinsurance recoverable	185,644	183,562
Deferred income taxes	2,797
Deferred acquisition costs	25,213	26,182
Funds on deposit	36,915	42,088
Other assets	18,431	25,849
Total assets	1,351,162	1,373,131	1,328,057
Unpaid losses and loss adjustment expenses	727,278	725,244
Unearned premiums	151,738	146,096
Ceded premiums payable	22,291	13,386
Funds held	61,642	76,806
Deferred income taxes		8,767
Total liabilities	1,017,099	1,028,083
VIE [Member]
Assets and Liabilities of the VIE as consolidated in the Consolidated Balance Sheets
Investments	11,798	12,144
Cash and cash equivalents	439	507
Accrued investment income	56	52
Premiums receivable	383	498
Ceded unearned premium	218	351
Reinsurance recoverable	4,659	5,039
Deferred income taxes	121	0
Deferred acquisition costs	715	1,100
Funds on deposit	114	231
Other assets	724	1,255
Total assets	19,227	21,177
Unpaid losses and loss adjustment expenses	8,398	8,900
Unearned premiums	2,878	4,325
Ceded premiums payable	326	67
Funds held	99	113
Deferred income taxes	0	30
Total liabilities	$ 11,701	$ 13,435