Motor Fuels Taxes Payable Accrued Expenses and Other Current Liabilities (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Motor Fuels Taxes Payable and Accrued Expenses and Other Current Liabilities
Interest expense	$ 130	$ 124
Professional fees	1,100	436
Express Lane working capital payable	1,791	1,791
Other items, net	1,646	948
Total accrued expenses and other current liabilities	$ 4,667	$ 3,299