Investments (Details 2) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Fair Value 12 months or less	$ 56,756	$ 81,876
Unrealized Losses 12 months or less	(1,442)	(1,047)
Fair Value Longer than 12 months	51,652	50,039
Unrealized Losses Longer than 12 months	(3,131)	(3,782)
Total Fair Value	108,408	131,915
Total Unrealized Losses	(4,573)	(4,829)
Equity Securities [Member]
Fair Value 12 months or less	2,368	3,363
Unrealized Losses 12 months or less	(888)	(515)
Fair Value Longer than 12 months	0	0
Unrealized Losses Longer than 12 months	0	0
Total Fair Value	2,368	3,363
Total Unrealized Losses	(888)	(515)
Debt Securities [Member]
Fair Value 12 months or less	54,388	78,513
Unrealized Losses 12 months or less	(554)	(532)
Fair Value Longer than 12 months	51,652	50,039
Unrealized Losses Longer than 12 months	(3,131)	(3,782)
Total Fair Value	106,040	128,552
Total Unrealized Losses	(3,685)	(4,314)
US Treasury Securities and Obligation [Member] | Debt Securities [Member]
Fair Value 12 months or less	0	23,998
Unrealized Losses 12 months or less	0	(3)
Fair Value Longer than 12 months	0	0
Unrealized Losses Longer than 12 months	0	0
Total Fair Value	0	23,998
Total Unrealized Losses	0	(3)
Corporate Bond Securities [Member] | Debt Securities [Member]
Fair Value 12 months or less	5,072	10,802
Unrealized Losses 12 months or less	(55)	(38)
Fair Value Longer than 12 months	6,301	6,910
Unrealized Losses Longer than 12 months	(854)	(725)
Total Fair Value	11,373	17,712
Total Unrealized Losses	(909)	(763)
Collateralized Corporate Bank Loans [Member] | Debt Securities [Member]
Fair Value 12 months or less	6,844	6,273
Unrealized Losses 12 months or less	(90)	(97)
Fair Value Longer than 12 months	10,354	14,236
Unrealized Losses Longer than 12 months	(225)	(646)
Total Fair Value	17,198	20,509
Total Unrealized Losses	(315)	(743)
Municipal Bonds [Member] | Debt Securities [Member]
Fair Value 12 months or less	24,459	30,073
Unrealized Losses 12 months or less	(273)	(362)
Fair Value Longer than 12 months	34,894	28,809
Unrealized Losses Longer than 12 months	(2,049)	(2,408)
Total Fair Value	59,353	58,882
Total Unrealized Losses	(2,322)	(2,770)
Collateralized Mortgage Backed Securities [Member] | Debt Securities [Member]
Fair Value 12 months or less	18,013	7,367
Unrealized Losses 12 months or less	(136)	(32)
Fair Value Longer than 12 months	103	84
Unrealized Losses Longer than 12 months	(3)	(3)
Total Fair Value	18,116	7,451
Total Unrealized Losses	(139)	(35)
Equity Securities Financial Services [Member] | Equity Securities [Member]
Fair Value 12 months or less	0	92
Unrealized Losses 12 months or less	0	(1)
Fair Value Longer than 12 months	0	0
Unrealized Losses Longer than 12 months	0	0
Total Fair Value	0	92
Total Unrealized Losses	0	(1)
Equity Securities, Other [Member] | Equity Securities [Member]
Fair Value 12 months or less	2,368	3,271
Unrealized Losses 12 months or less	(888)	(514)
Fair Value Longer than 12 months	0	0
Unrealized Losses Longer than 12 months	0	0
Total Fair Value	2,368	3,271
Total Unrealized Losses	$ (888)	$ (514)