Investments (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Investment in Marketable Securities (Textual) [Abstract]
Unrealized gain (loss) on available for sale securities	$ (931)	$ (1,086)	$ (3,744)	$ (1,487)
Impairment of equity securities	(483)	$ (1,092)	(2,028)	$ (4,614)
Marketable securities [Member]
Available-for-sale Securities
Cost	3,730		3,730		$ 5,687
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	1,196		1,196		8
Available-for-sale Equity Securities, Accumulated Gross Unrealized Gain, before Tax	679		679		303
Available-for-sale Securities, Estimated Fair Value	3,213		3,213		$ 5,982
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value [Abstract]
Less than twelve Months, Fair Value	1,017		1,017
Twelve months or more, Fair Value	0		0
Fair Value	1,017		1,017
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	$ 1,196		$ 1,196