Leases (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Leases, Operating [Abstract]
2013	$ 1,604
2014	1,604
2015	600
Total	3,808
Lease expiration date	Jun. 10, 2015
Rental expense under non-cancelable revenue equipment operating leases	$ 1,620	$ 1,012