Schedule II - Condensed Financial Information of Registrant (Parent Company Only) (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Cash flows from operating activities:
Net income (loss)	$ 1,783	$ 3,671	$ (1,800)	$ 194	$ 341	$ 104	$ (79)	$ (11,199)	$ 3,848	$ (10,833)	$ 7,508
Adjustments to reconcile net income (loss) to cash provided by (used in) operating activities:
Depreciation and amortization expense									4,421	5,064	4,751
Deferred income tax benefit									(2,851)	(2,895)	(980)
Realized loss									(1,943)	(3,633)	(8,402)
Change in all other liabilities									5,396	(5,707)	(2,040)
Change in all other assets									5,983	3,587	4,411
Net cash provided by (used in) operating activities									33,682	24,610	36,360
Cash flows from investing activities:
Purchases of property and equipment									(107)	(1,586)	(1,775)
Purchase of fixed maturity and equity securities									(167,626)	(265,684)	(226,246)
Maturities and redemptions of investment securities									148,968	280,918	134,821
Net cash (used in) provided by investing activities									(18,100)	(3,781)	(87,992)
Cash flows from financing activities:
Proceeds from exercise of employee stock options									0	99	25
Purchase of treasury shares									0	(6,401)	0
Activity under revolving credit facility, net									(2,577)	1,250	0
Net cash (used in) provided by financing activities									(4,908)	(6,877)	(119)
(Decrease) increase in cash and cash equivalents									10,674	13,952	(51,751)
Cash and cash equivalents at beginning of year				74,471				60,519	74,471	60,519	112,270
Cash and cash equivalents at end of year	85,145				74,471				85,145	74,471	60,519
Supplemental cash flow information:
Interest paid									(4,656)	(4,620)	(4,594)
Income taxes recovered (paid)									5,879	3,589	(7,202)
Parent Company [Member]
Cash flows from operating activities:
Net income (loss)									3,524	(10,891)	7,403
Adjustments to reconcile net income (loss) to cash provided by (used in) operating activities:
Depreciation and amortization expense									113	168	223
Deferred income tax benefit									(1,725)	(215)	(12)
Undistributed share of (earnings) loss of subsidiaries									(6,323)	7,130	(11,430)
Realized loss									0	0	(41)
Change in current federal income tax payable (recoverable)									4,030	(4,838)	(700)
Change in all other liabilities									357	5,155	4,092
Change in all other assets									450	1,074	838
Net cash provided by (used in) operating activities									426	(2,417)	373
Cash flows from investing activities:
Purchases of property and equipment									(46)	(205)	(28)
Purchase of fixed maturity and equity securities									0	0	(989)
Maturities and redemptions of investment securities									0	0	1,956
Net cash (used in) provided by investing activities									(46)	(205)	939
Cash flows from financing activities:
Proceeds from exercise of employee stock options									0	99	25
Purchase of treasury shares									0	(6,401)	0
Activity under revolving credit facility, net									(2,577)	1,250	0
Net cash (used in) provided by financing activities									(2,577)	(5,052)	25
(Decrease) increase in cash and cash equivalents									(2,197)	(7,674)	1,337
Cash and cash equivalents at beginning of year				3,309				10,983	3,309	10,983	9,646
Cash and cash equivalents at end of year	1,112				3,309				1,112	3,309	10,983
Supplemental cash flow information:
Interest paid									(4,656)	(4,620)	(4,594)
Income taxes recovered (paid)									$ 3,932	$ (3,383)	$ 895