Marketable Securities (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended	12 Months Ended
	Sep. 30, 2014 investment	Dec. 31, 2013 investment
Schedule of Available-for-sale Securities [Line Items]
Total number in loss position (investments)	1	1
Less than twelve months - fair values	$ 9,630	$ 12,460
Less than twelve months - unrealized losses	(126)	(229)
Twelve months or greater - fair values	0	0
Twelve months or greater - unrealized losses	0	0
Total Fair Value	9,630	12,460
Total Unrealized Losses	(126)	(229)
Mutual Funds [Member]
Schedule of Available-for-sale Securities [Line Items]
Total number in loss position (investments)	1	1
Less than twelve months - fair values	9,630	12,460
Less than twelve months - unrealized losses	(126)	(229)
Twelve months or greater - fair values	0	0
Twelve months or greater - unrealized losses	0	0
Total Fair Value	9,630	12,460
Total Unrealized Losses	$ (126)	$ (229)
Unrestricted Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Investments with other than temporary impairments (investments)	0