Fair Value Measurements (Marketable Debt Securities) (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended	12 Months Ended
	Jun. 30, 2014	Dec. 31, 2013
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Amortized Cost	$ 11,012	$ 11,364
Gross Unrealized Gains	92	83
Gross Unrealized Losses	0	(2)
Estimated Fair Value	11,104	11,445
Other-than-temporary Impairments	0	0
Municipal bonds - available for sale [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Amortized Cost	11,012	11,364
Gross Unrealized Gains	92	83
Gross Unrealized Losses	0	(2)
Estimated Fair Value	11,104	11,445
Other-than-temporary Impairments	$ 0	$ 0