Investments (Summary of Gross Unrealized Losses for Investments that have been Continuously in Unrealized Loss Position) (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended	12 Months Ended
	Jun. 30, 2014	Dec. 31, 2013
Schedule of Investments [Line Items]
Fair Value 12 months or less	$ 98,531	$ 113,255
Unrealized Losses 12 months or less	(1,192)	(1,287)
Fair Value Longer than 12 months	36,042	53,634
Unrealized Losses Longer than 12 months	(1,666)	(2,613)
Total Fair Value	134,573	166,889
Total Unrealized Losses	(2,858)	(3,900)
Equity Securities [Member]
Schedule of Investments [Line Items]
Fair Value 12 months or less	579	316
Unrealized Losses 12 months or less	(2)	(2)
Fair Value Longer than 12 months		2,721
Unrealized Losses Longer than 12 months		(312)
Total Fair Value	579	3,037
Total Unrealized Losses	(2)	(314)
Debt Securities [Member]
Schedule of Investments [Line Items]
Fair Value 12 months or less	97,952	112,939
Unrealized Losses 12 months or less	(1,190)	(1,285)
Fair Value Longer than 12 months	36,042	50,913
Unrealized Losses Longer than 12 months	(1,666)	(2,301)
Total Fair Value	133,994	163,852
Total Unrealized Losses	(2,856)	(3,586)
US Treasury Securities and Obligations of U.S. Government [Member] | Debt Securities [Member]
Schedule of Investments [Line Items]
Fair Value 12 months or less	14,770	47,162
Unrealized Losses 12 months or less	(3)	(165)
Total Fair Value	14,770	47,162
Total Unrealized Losses	(3)	(165)
Corporate Bonds [Member] | Debt Securities [Member]
Schedule of Investments [Line Items]
Fair Value 12 months or less	3,344	5,649
Unrealized Losses 12 months or less	(17)	(56)
Fair Value Longer than 12 months		4,421
Unrealized Losses Longer than 12 months		(394)
Total Fair Value	3,344	10,070
Total Unrealized Losses	(17)	(450)
Collateralized Corporate Bank Loans [Member] | Debt Securities [Member]
Schedule of Investments [Line Items]
Fair Value 12 months or less	32,977	23,026
Unrealized Losses 12 months or less	(761)	(422)
Fair Value Longer than 12 months	5,902	6,968
Unrealized Losses Longer than 12 months	(76)	(67)
Total Fair Value	38,879	29,994
Total Unrealized Losses	(837)	(489)
Municipal Bonds [Member] | Debt Securities [Member]
Schedule of Investments [Line Items]
Fair Value 12 months or less	24,360	35,719
Unrealized Losses 12 months or less	(205)	(413)
Fair Value Longer than 12 months	26,097	34,684
Unrealized Losses Longer than 12 months	(1,086)	(1,562)
Total Fair Value	50,457	70,403
Total Unrealized Losses	(1,291)	(1,975)
Mortgage Backed [Member] | Debt Securities [Member]
Schedule of Investments [Line Items]
Fair Value 12 months or less	22,501	1,383
Unrealized Losses 12 months or less	(204)	(229)
Fair Value Longer than 12 months	4,043	4,840
Unrealized Losses Longer than 12 months	(504)	(278)
Total Fair Value	26,544	6,223
Total Unrealized Losses	$ (708)	$ (507)