Track Maintenance Agreement (Details Textual) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended	12 Months Ended
	Jun. 30, 2012	Jun. 30, 2012	Dec. 31, 2011
Track Maintenance Agreement (Textual) [Abstract]
Track maintenance revenue from third party	$ 0	$ 0	$ 869