Investments (Summary of Realized Gain (Loss) on Investments) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Schedule of Investments [Line Items]
Gain on investments	$ 185	$ 1,176
Net realized gains	185	1,176
Us Treasury Securities and Obligations of U.S. Government [Member]
Schedule of Investments [Line Items]
Gain on investments
Corporate Bonds [Member]
Schedule of Investments [Line Items]
Gain on investments	154	358
Collateralized Corporate Bank Loans [Member]
Schedule of Investments [Line Items]
Gain on investments	59	173
Municipal Bonds [Member]
Schedule of Investments [Line Items]
Gain on investments	(28)	(8)
All Other [Member]
Schedule of Investments [Line Items]
Gain on investments		$ 653